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An algorithm for three-axis NC tool path generation on sculptured surfaces is presented. Non-constant parameter tool contact curves are defined on the part by intersecting parallel planes with the part model surface Four essential elements of this algorithm are introduced: initial chordal approximation, true machining error calculation, direct gouge elimination, and non-constant parameter tool pass interval adjustment. A software implementation of this algorithm produces graphical output depicting the tool path superimposed over the part surface, and it outputs cutter location (CL) data for further postprocessing. Several applications examples are presented to demonstrate the capabilities of the algorithm The results of this technique are compared to those generated from a commercially available computer-aided manufacturing program, and indicate that equivalent accuracy is obtained with many fewer CL points.

Modifications of spermatogenesis and anatomy of male reproductive tracts caused by radiation (fast electrons) are described in Acarus siro and compared with data from other arthropod taxa. Radiation induced severe changes in gonial cells, including dilatation of endoplasmic reticulum and disruption of mitochondrial cristae. The latter sometimes created roundish myelin structures inside the mitochondrial matrix. Damage in developing cells caused an interruption of spermatogenesis and reduced the number of spermatids produced; high doses can cause sterility.

Collaborative work has became an increasingly crucial aspect of engineering design as teams grow larger and more diverse. However, the complexity of the CAD system's interface can introduce a participation barrier. In a design review context, this barrier prevents the diverse team members from directly interacting with the CAD objects. The goal of the research presented in this paper is to consider an alternative to two-dimensional desktop-based interfaces for a design review. Using an augmented reality technology, we present a set of tangible user interfaces that allows the users to see virtual three-dimensional models and to manipulate them naturally as if they were real, physical objects.

An internal transcribed spacer (ITS2) sequence between the 5.8S and 28S rRNA genes was used to estimate the phyletic relationships among Ixodes spp. tick vectors of Lyme disease-causing Borrelia spirochetes. Analysis indicates that Borrelia burgdorferi sensu lato species associated with Lyme disease are found mainly in ticks of the Ixodes ricinus species complex. Other closely related tick species are not known to transmit the Borrelia-that cause Lyme disease in humans, but they appear to have a specific association with other closely related Borrelia species. There is a high degree of concordance in the phylogenetics of Borrelia taxa and the phylogenetic relationships among Ixodes ticks.

Ticks and blood samples were collected from wild birds mist-netted on St. Catherine's Island, Georgia, and at the Wedge Plan- tation in coastal South Carolina in 1994 and 1995. Immature stages of 5 species of ixodid ticks were recovered from 10 of 148 (7%) birds belonging to 6 species in Georgia, whereas 6 ixodid species were re- covered from 45 of 259 (17%) birds representing 10 avian species in South Carolina. Borrelia burgdorferi sensu lato was isolated from 27 of 120 (23%) screened ticks (Ixodes scapularis and Ixodes minor) re- covered from South Carolina birds, but from none of 16 screened ticks removed from Georgia birds. This spirochete was also isolated from 1 of 97 (1%) birds in South Carolina. In 1995, neither eastern equine encephalitis (EEE) virus nor St. Louis encephalitis (SLE) virus was isolated from any of 218 bird sera screened, but serum neutralizing antibodies were found to EEE virus in 4 of 121 (3%) sera and to SLE virus in 2 of 121 (2%) sera from South Carolina. No antibody to either virus was detected in 51 avian sera screened from Georgia. Trypano- somes (probably Trypanosoma avium) were isolated from 1 of 51 (2%) birds from Georgia and from 13 of 97 (13%) birds from South Carolina. Our data suggest that some wild birds may be reservoir hosts for the Lyme disease spirochete and for encephalitis viruses in coastal Georgia and South Carolina and that migrating birds can disperse immature ticks infected with B. burgdorferi.

We collected ectoparasites from eastern woodrats, Neotoma floridana, from 3 sites in the southeastern United States: coastal South Carolina, southeast Georgia, and south-central Georgia. Twelve ectoparasite species were recovered from 47 woodrats in South Carolina (5 ticks, 5 mites, 2 fleas), 13 from 35 woodrats in south-central Georgia (1 tick, 10 mites, 2 fleas), and 4 from a small host sample (7) in southeast Georgia (2 ticks, 1 mite, 1 flea). New state records are established for the listrophorid mite Listrophorus neotomae from both Georgia and South Carolina, the myocoptid mite Myocoptes neotomae from Georgia, and the ceratophyllid flea Orchopeas sexdentatus pennsylvanicus from South Carolina. Different ectoparasites predominated on woodrats at each site with the tick Ixodes minor being the most commonly collected species in South Carolina, the American dog tick Dermacentor variabilis in southeast Georgia, and the chigger Euschoengastia peromysci in south-central Georgia. Most of the 17 species recovered are known to parasitize several species of mammals, especially rodents, and none of them are host specific to N. floridana. However, the fleas Epitedia cavernicola and Epitedia neotomae are host-specific ectoparasites of eastern woodrats in other parts of their range. Also, 1 species of tick, 2 mites, and 3 fleas parasitize eastern woodrats in addition to western woodrats. A similar lack of host specificity is apparent for the few previously documented collections of ectoparasites from eastern woodrats, including 1 detailed survey in Indiana. Conversely, Neotoma spp. woodrats inhabiting western North America are parasitized by a plethora of host-specific ectoparasites including 2 tick species, 5 mites (other than chiggers), 20 chiggers, 2 sucking lice, and 42 fleas. Recognizing that western biotas are typically more speciose than corresponding eastern biotas in North America, we further propose that because eastern woodrats are the most recent and eastern descendants of the ancestral Neotoma stock, (1) some ectoparasite species failed to accompany the eastern woodrat lineage in its eastward dispersals, and (2) there has been insufficient time for a diverse assemblage of ectoparasites to co-evolve with eastern woodrats.

Lyme borreliosis (Lyme disease) is the most often reported arthropod transmitted disease in humans in the U.S.A. Although it has been reported from 43 states, cases are especially abundant in the mid-Atlantic and northeastern regions. Borrelia burgdorferi, the etiologic agent, is transmitted primarily by the western blacklegged tick (Ixodes pacificus) in far western North America, and by the blacklegged tick (Ixodes scapularis) in eastern North America. Although Lyme disease cases have been reported from southern states, some researchers doubt the presence of B. burgdorferi or of human Lyme disease in the south. However, new data show that B. burgdorferi is widely distributed in the south and that strains are genetically more varied than in the north. Moreover, B. burgdorferi enzootic cycles appear to be more complex and more tick species are identified as vectors of the spirochete in the southern states.

From 1990 through 1995, 913 ticks removed from 460 human patients in Georgia or South Carolina were identified and recorded. The majority of these specimens (758, 83.0%) were lone star ticks, Amblyomma americanum. One hundred and four (11.4%) American dog ticks Dermacentor variabilis, 36 (3.9%) blacklegged ticks Ixodes scapularis, 9 (1.0%) Gulf coast ticks Amblyomma maculatum, and 6 (0.7%) brown dog ticks Rhipicephalus sanguineus were also recovered. All active stages (larvae, nymphs, and adults) of A. americanum were represented, whereas nymphs and adults of D. variabilis and I. scapularis and only adults of A. maculatum and R. sanguineus were recorded. Compared with data published for other regions in the U.S.A., A. americanum was a much more prevalent parasite of humans in the current survey. Only 1 (3%) of the I. scapularis collected was a nymph. Because these tick species are vectors of zoonotic pathogens or cause tick paralysis in humans, the data have epidemiological significance.

Quantitative tick drag samples were taken at various times during the day and night from February through April 1994 on St. Catherines Island or on Sapelo Island, Georgia. For each month, there was no statistical difference between the numbers of adult blacklegged ticks, Ixodes scapularis, collected during any hour of daylight or darkness on St. Catherines Island, Adult I. scapularis also quested during both day and night on Sapelo Island, but on this island significantly more ticks were collected in 1 nocturnal sample during March. Nocturnal questing may partially explain why hosts that are principally nocturnal or that are active during both day and night are often heavily parasitized by adult I. scapularis. This observation could be epidemiologically important with respect to tickborne zoonoses such as Lyme disease and babesiosis.

The male of Amblyomma rotundatum is described for the first time, and the nymph and larva are redescribed. This tick is a parthenogenetically reproducing species parasitic on amphibians and reptiles in the warmer areas of the New World. Attempts to mate male and female A. rotundatum under laboratory conditions were unsuccessful.

The parthenogenetic tick Amblyomma rotundatum, a Central and South American species, has become established in southern Florida. The date of introduction is unknown, but it is suspected to be either during the 1930s, when 1 of its natural hosts, the giant or marine toad, Bufo marinus, was introduced to southern Florida as a potential biological control of pest beetles in sugar cane fields, or between 1955 and 1964 when specimens of B. marinus were accidentally or deliberately released in the greater Miami area. Several museum specimens of this toad collected in the Miami area 25 April 1979 had nymphal and adult A. rotundatum attached. Subsequent examination of living giant toads collected at another Miami area site from 1983 through 1985 revealed larval, nymphal, and adult A. rotundatum and confirmed colonization of this tick. Under laboratory conditions, another neotropical amphibian and reptile tick, Amblyomma dissimile, is capable of transmitting Cowdria ruminantium, the causative agent of heartwater, a disease present in the Caribbean area. Therefore, we suggest that A. rotundatum should also be tested for vectorial competence.

Preserved museum specimens of 13 lizard and 3 snake species common in the southeastern U.S.A. were examined for immature Ixodes scapularis Say ticks. Five Eumeces and 4 Ophisaurus lizard species yielded an infestation prevalence of 17.8% for species of Eumeces and 29.0% for species of Ophisaurus. Mean intensity of larvae and nymphs was 7.1 and 2.7, respectively, for species of Eumeces, and 6.3 and 1.4, respectively, for species of Ophisaurus. Collection dates of the lizards ranged from January through December, but most were collected from March through October. The maximum number of immatures found on a single specimen was 193 larvae and 11 nymphs on a specimen of Eumeces and 75 larvae and 7 nymphs on a specimen of Ophisaurus. For species of Eumeces, 75.2% of all nymphs observed were attached in the shoulder area. Larvae were most abundant on the rear legs (53.3%), followed by the front legs (26.3%) and shoulders (12.9%). Larvae and nymphs on species of Ophisaurus were found almost exclusively in the lateral groove area (84.0% and 94.4%, respectively). Three other lizard species (Anolis carolinensis, Sceloporus undulatus, Scincella lateralis) had only a few ticks or none. A fourth species, Cnemidophorus sexlineatus, hosted a total of 3 larvae on 3 specimens (infestation prevalence, 10.7%). Three snake species (Diadophis punctatus, Virginia striatula, Crotalus adamanteus) had none.

The structure of Haller's organ in all major groups of soft ticks, family Argasidae, is reexamined, and hypotheses of setal homology are proposed based on a comparative study of developmental patterns. The larvae of most taxa have 7 setae in the anterior pit (1 serrate, 1 conical, 2 fine, 2 porose, 1 grooved) and 4 porose setae in the capsule. The postlarval stages add up to 3 setae to the anterior pit (1 serrate, 1 porose, 1 grooved) and up to 3 porose setae to the capsule. Preliminary hypotheses of polarity, distinguishing ancestral from derived character states, are generated for most characters examined by comparisons with results obtained for the other major family of ticks, Ixodidae, and (where possible) other members of Parasitiformes. Most of the variability in the setal complement of the anterior pit and capsule results from paedomorphosis, and nearly all the observed changes in the setal complement (both modifications of addition patterns and changes in fundamental numbers) are restricted to single species or small species groups. A correlation between changes in Haller's organ structure and changes in life history patterns is suggested but cannot be confirmed based on presently available data.

The role of the synganglion in oocyte development in Ornithodoros parkeri was investigated by ligation and transplantation experiments. Ligation between legs 2 and 3 to isolate the synganglion from the ovary and ligation between legs 1 and 2 to keep both the synganglion and the ovary in the posterior ends were performed on mated females on different days after feeding. Results show that vitellogenesis was inhibited significantly if the synganglion was separated from the ovary within the first few days after feeding. However, transplantation of synganglia from 3 kinds of donors (unfed virgin, fed virgin, and fed mated females) into the synganglionless posterior portions induced vitellogenesis and oocyte development to final maturation. The supra- and subesophageal parts of the synganglion showed a similar gonadotropic activity after each was transplanted separately into the ligated synganglionless posterior portions. These results indicate that the synganglion produces an egg development stimulation factor (EDSF) that possibly is present in a storage form in unfed and/or fed virgin females in which vitellogenesis has not progressed and is released in females after feeding and mating. However, the characterization of EDSF and precise sites of production and storage await further investigation.

Male Amblyomma dissimile possess 10 autosomal bivalents and 1 sex univalent chromosome. Anaphase I is the reductional division, and anaphase II is the equational division for the single sex chromosome. Chromosomal configurations indicate terminal centromeres on all chromosomes. Mitotic cells show 20 autosomes plus 1 sex chromosome. Individuals of all developmental stages of this species feed on reptiles, and only larvae also feed readily on rabbits. Developmental periods are more variable than those usually seen in mammalian tick parasites, and adults congregate in close proximity to one another while feeding. Individual females vary in their expression of parthenogenesis (thelytoky) from producing eggs with no embryonic development to fully embryonated eggs, some of which hatch.

Diploid Ornithonyssus bacoti females from an inbred laboratory colony are more variable in more external morphological characters than haploid males maintained under identical colony conditions. Prejudiced selection of characters or use of a small sample size can provide data suggesting greater variability in males. When large numbers of characters on many mite specimens are compared by F-tests of variances, coefficients of variation, generalized variances (determinant of variance-covariance matrices) and tests of homogeneity of variance-covariance matrices, general phenotypic variation is greater in females. The agreement between univariate and multivariate tests allows additional confidence in the conclusion (tables 2–7).

Eggs of the American dog tick were treated by immersion at two embryonic stages (72–84 and 168–180 h old) with metepa in acetone (1, 3, and 5 μg/μl concentrations). Hatching occurred at all metepa concentrations in both developmental groups, although percent hatch was significantly reduced in eggs exposed at 72–84 h. Immature ticks were treated topically with metepa as unfed larvae, 1-day postengorgement larvae, unfed nymphs, and nymphs 1, 7, and 14 days postengorgement. The number of treated, unfed larvae and unfed nymphs that successfully attached and engorged was significantly reduced, and those that engorged failed to ecdyse. Larvae and nymphs treated 1 day postengorgement failed to ecdyse. Nymphs treated 7 and 14 days postengorgement ecdysed to adults at all concentrations (acetone control, 1, 3, and 5 μg/μl). Testes of ticks treated as 7-day postengorgement nymphs developed normally, but testes of the 14-day postengorgement treatment group were reduced in size.

Khalil G. M. , Hoogstraal H. and Oliver J. H. Jr. 1980. Biological evaluation of the systematic validity of the African Argas (Persicargas) arboreus and the Asian-Australian A.(P.)robertsi (Ixodoidea: Argasidae). International journal for Parasitology 10 : 253–259. The closely related A. (P.) arboreus (Ethiopian Faunal Region) and A. (P.) robertsi (Oriental and Australian Faunal Regions) interbreed readily and produce partially fertile progeny. Intrahybrid crosses are much less productive than P 1 homogamic crosses. Results of backcrosses indicate that the progeny of the robertsi ♂ × arboreus ♀ cross are less fertile than the progeny of the reciprocal cross. The fertility of F 1 hybrid progeny is lower than that of the P 1 pure species as expressed in lower female fecundity, egg hatch, and/or viability of immature stages. These 2 species probably originated from a common ancestor and geographic isolation caused genetic incompatibility.

Injected [3H] precocene-II spread from the hemocoel of Ornithodoros parkeri (Cooley) ticks to gut, salivary glands, synganglion, ovary, and the remainder of the body (carcass). Analyses at 2, 24, and 48 h after injection of precocene revealed that radioactivity remained at low levels in the synganglia and ovaries of fed-mated and fed-virgin females. Radioactivity increased gradually during 48 h after injection in salivary glands of fed-mated and fed-virgin ticks. It also increased gradually in the gut of fed virgins but not in fedmated females. The carcasses contained the majority of total radioactivity at 2, 24, and 48 h after injection. Most of the radioactivity was found in ether-soluble compounds and only minimal amounts in water-soluble metabolites. Analysis of tick excreta and washings indicate that female O. parkeri excrete injected precocene very slowly; only 6% of total radioactivity was recovered in these samples during the 48 h after injection. Thin-layer chromatographic analyses of ether extracts of salivary glands and carcasses from fed-mated ticks 24 h after injection showed that the majority of the injected [3H] precocene-II was present in unchanged form.

The effects of metepa on the cytology and fertility of male Dermacentor variabilis (Say) treated at 2 nutritional states were determined. Cellular damage was found in posterior testicular areas in ticks fed for 3 days prior to treatment and in anterior testicular areas in those fed 6 days prior to treatment. These areas correspond to the respective areas where actively dividing spermatocytes and elongating spermatids are located. The amount of cellular damage correlated positively to the concentration of metepa applied. Egg masses from untreated female × treated male crosses hatched normally, but variations were noted in fecundity, engorgement, and preovipositional and incubation periods.

The maturation of tick (Acari: Ixodoidea) spermatozoa, after their transfer to the female, is induced by secretions of the male accessory gland which are added to the prospermia during ejaculation. Analysis of the secretions from male Ornithodoros moubata (Argasidae) and Dermacentor variabilis (Ixodidae) indicates that the factor responsible for inducing maturation is a polypeptide with a molecular weight of about 12,500. Although the polypeptides from the two species are similar in most respects, each will not activate the prospermia of the other species. The mode of action of the factor is hormone-like, inasmuch as a few minutes of exposure of the sperm to the factor are sufficient to trigger the entire maturation sequence, which takes 12–24 h in vitro.

Histological techniques and paraldehyde-fuchsin (PAF) staining were used to study the synganglion and to locate neurosecretory regions and neurosecretion within the synganglion of the chicken mite, Dermanyssus gallinae. The synganglion, which is formed internally by neuropilar ganglia, gives rise to a single esophageal and paired cheliceral, palpal, pedal (I-IV), and opisthosomal nerves. The neuropilar ganglia are interconnected by commissures and connectives within the synganglion. Twelve PAF-positive neurosecretory regions are present in unfed protonymphs, unfed deutonymphs, virgin males and females, and mated males. There are 11 PAF-positive neurosecretory regions in larvae, 24-72 hours post-fed deutonymphs and mated females. Neurosecretory regions in these developmental stadia are described in relation to their positions adjacent to individual neuropilar ganglia.

Reproduction in ticks is discussed under the following: gametogenesis, meeting of the sexes, copulation, spermatophores, sperm relocation, syngamy, sperm longevity, and oviposition. The relationships among gametogenesis, copulation, oviposition and feeding are emphasized. Speculative suggestions as well as published and unpublished data are provided.

Dermanyssus gallinae mites consistently aggregate and form clusters of mixed developmental stages; recently fed mites aggregate most quickly and form more definite clusters than unfed mites. Thigmokinesis and pheromones are involved in the clustering behavior. The aggregation pheromone(s) is volatile and can be recognized by mites without directly contacting it. D. gallinae is not attracted (or if so, only weakly) to several synthetic chemicals that are reported to function as pheromones in other acarine taxa. It is somewhat attracted to synthetic guanine.

The tick Aponomma varanensis attached to a king cobra ( Ophiophagus hannah ) was accidentally imported into the United States and was discovered at the Bronx Zoo. Two generations of tick progeny were reared and investigated under laboratory conditions. A. varanensis males possess 21 chromosomes (20 autosomes and 1 sex chromosome). The processes of spermatogenesis and spermiogenesis are similar to those found in other ticks. However, the males are unusual in that timing of meiosis and spermatid production are not as synchronized among individuals as in other metastriate ticks, and they produce elongated spermatids without having a blood meal. Although elongated spermatids were present in unfed males, they were not transferred to females off the host under our experimental conditions. All stages of A. varanensis fed successfully on rat snakes ( Elaphe obsoleta ). Larvae also fed on eastern box turtles ( Terrapene Carolina ), but not southern toads ( Bufo terrestris ), five-lined skinks ( Eumeces fasciatus ), or laboratory mice ( Mus musculus ). Most of the A. varanensis behaved similarly to a typical three-host tick and dropped from the host after each feeding, but approximately 3% of fed larvae remained attached and ecdysed on the host, and the resulting nymphs immediately began feeding. Unfed larvae were exceptionally long-lived (more than 22 mo).

Histological observations using specialized techniques reveal neurosecretory cells in 18 centers throughout the rind (cortex) of the central nerve mass or synganglion of Dermacentor variabilis. Many cells contribute to complicated networks of neurosecretory pathways and tracts in pre- and post-esophageal portions of the synganglion. The four types of neurohemal-neuroendocrine associations found in Dermacentor resemble structures found in soft ticks (Argasidae) and in other Arachnida, but are more diverse than those described from any other single species. Neurosecretory terminals are distributed diffusely and in two concentrated associations within the perineurium of the synganglion and major peripheral nerves. Terminals are also distributed in the perineurial layers of lateral segmental organs which lie in the general hemocoel at the level of the pedal nerves. A retrocerebral organ complex surrounds the esophagus at its junction with the midgut. The complex includes dorsal and ventro-lateral lobes (containing neurosecretory terminals and intrinsic secretory cells1 and the proventricular (neurohemal) plexus. This plexus seems to be a modified (concentrated) cardioglial association. Cardioglial associations are also formed by the neurosecretory innervation of vascular walls of the dorsal aorta and circulatory sinuses which envelope the synganglion and major peripheral nerves. Inferential considerations of neurosecretory and endocrine interactions in the Acari are based on these anatomical and histological data which also provide the basis for evolutionary considerations of anatomical relationships and specializations in the neurosecretory systems of other Arachnida.

When fed males of Amblyomma hebraeum were confined with unfed females of A. variegatum under sleeves on the backs of rabbits, pairing occurred and the females engorged and produced egg masses. Similar results were obtained with the reciprocal cross. Although interspecific matings occurred, conspecific matings outnumbered them when ticks were given a choice. A species-specific pheromone is speculated as the critical specific recognition factor, but physical recognition factors are not eliminated. After males and females attached to hosts next to heterospecific ticks, they did not move 5 cm even to conspecific potential mates. All egg masses produced from interspecific matings were infertile (

Tick peripheral and central fat body (FB) contains distinct acidophilic and basophilic cell types. Previous workers call them trophocytes and nephrocytes, respectively, but overlapping physiological functions make histological descriptors more serviceable. Acidophils in Argasidae and Ixodidae contain sudanophilic vacuoles with localized caps showing nonspecific esterase activity. They are implicated in trophic lipid storage but also contain carbohydrate and protein. FB acidophils are also implicated in purine metabolism and may serve the function of insect urate cells. Basophils may contain abundant carbohydrate and protein but little lipid. Pinocytosis of dyes and incorporation of presumptive hemoglobin derivatives implicates them in deposit excretion. Pinocytosis by hemocytes, pericardial cells, Malpighian tubules and basophils indicates a probable division of labor in uptake of various sized particles from tick hemolymph. Differentiation of central FB is coordinated with maturation of reproductive organs, usually in response to adult blood meals. There is a simultaneous development of central and peripheral FB only in ixodid females. Timing and extent of FB differentiation implicates these tissues in vitellogenic processes associated with the extensive fecundity and strict gonotrophic requirements of female ixodids. Absence of peripheral differentiation in male ixodids and most argasids appears related to persistence of gonotrophic rhythms. Ixodid peripheral FB autolysis may be related to connective tissue formation or reproductive development but should also release tick symbiotes or agents of disease. Resulting increases in circulating titer should significantly affect the vector capacity of ixodid ticks.

Mating behavior, spermiogenesis, egg development time, and male mating capacity of Dermanyssus gallinae (DeGeer) (Parasitiformes: Dermanyssidae) are described. Insemination is podospermal, via spermadactyls inserted into sperm induction pores located on each side of the body (podosoma) near the posterior of coxae III. Mating behavior is of the Amblyseius-Typhlodromus type, requiring 14 min to 1 h. One or both sperm induction pores may be used. Spermatophores isolated during mating were spherical, translucent, permeable to stain, and approximately 200 μm in diameter with a smaller neck where they were held by male chelicerae. Observation and measurement of approximately 200 spermatozoa from male reproductive tracts, spermatophores, and unfed and fed mated females indicate that spermatozoa in this species do not develop beyond irregularly rounded nonpolar cells with granular cell membranes, agranular cytoplasm, and large, densely stained nuclei with average cellular and nuclear dimensions of 7.80 by 11.73 and 3.70 by 4.09 μm, respectively. Several spermatozoa were observed in medial ovarian tissue of unfed females 1d after mating, and spermatozoa were not found in five unfed females 32 d after mating. Egg maturation and protonymphal development appear staggered, not synchronous. Males probably are incapable of successfully inseminating more than three or four females in the same number of days.

David P. Gardner, president of the University of California, noted in a recent editorial in Science (1987) that the United States and the nations that ring the Pacific Ocean are becoming increasingly interdependent. He quotes Professor Robett Scalapino of the University of California, Berkeley, Institute of East Asian Studies: “As far as the United States is concerned, the 21st Century is its Pacific Century.” Gardner's compelling editorial points out that more than half of the world's people live in the Asia-Pacific region. Politically, strategically, economically, and educationally, Asia has gained and will continue to gain even greater global significance.

Like many of you, my first contact with the name Robert L. Usinger was when I opened my General Zoology textbook and noticed that the authors were two professors with the names of Storer and Usinger. At that point in my life I never dreamed that I would meet one of them, let alone several years later be asked to read a section of a later edition of that book for accuracy of content.

Haemaphysalis longicornis consists of diploid bisexual races (20+ XX♀; 20+X♂), triploid obligatory parthenogenetic races (30–35 chromosomes) and an aneuploid race capable of bisexual and parthenogenetic reproduction (22–28 chromosomes). Karyotypes were analyzed for each race. Hybridization failed between diploid and triploid races, but succeeded between bisexual diploid males and parthenogenetic aneuploid females. F1 and F2 progeny were produced and their chromosomes studied. Crossing of F1 progeny to a bisexual race was successful. Parthenogenetic ability was almost completely lost in F1 and F2 females. Several possible modes of evolution from diploid bisexual individuals to triploid parthenogenetic ones are discussed as is species characterization in taxa with races reproducing bisexually, parthenogenetically and by a combination of both methods.

Political scientists interested in non-Communist systems have paid considerable attention to demands (expressions of opinion that an authoritative allocation with regard to particular subject matters should or should not be made by those responsible for doing so) coming from the intra-societal (domestic) environments of these political systems. The importance of intra-societal demands, including citizen demands, for non-Communist systems is well established. Researchers interested in the Soviet political system have paid relatively little attention to intra-societal demands, especially demands coming from those whom David Easton would call citizen gatekeepers, i.e., citizens who convert their wants into demands by articulating them.The reasons for the neglect of research in this area are obvious enough. Quite apart from the problem of gathering useful data, there exists the question of whether demands from the intra-societal environment, and in particular citizen demands, are really important for a “totalitarian” system. Nothing like the politically autonomous interest groups of the Western democracies exist in the Soviet Union. Whatever demands come from the intra-societal environment are therefore largely grassroots demands from the populace, and there is reason to doubt that Soviet authorities feel compelled to heed such demands when formulating policy. Lenin's assertion that the Party is the vanguard of the proletariat was clearly a rejection of the idea that the masses should direct the Party. His successors have continued to assert that the Party leads the masses, and not the masses the Party.

Various aspects of reproductive behavior were investigated in the mites Dermanyssus gallinae, Ophionyssus natricis, Ornithonyssus bacoti , and Ornithonyssus sylviarum. Results of observations and experiments were compared on such topics as: the effect of mating on feeding, oviposition and longevity of the females; effect of feeding on mating; site of mating; longevity of spermatozoa in the female; and multiple mated females' effect on sex ratio of progeny.

The chromosome complements of 2 argasid ticks, Ornithodoros (Pavlovskyella) macmillani Hoogstraal and Kohls and O . ( P .) gurneyi Warburton, are described and compared with 5 other chromosomally known species of the subgenus. Four of these 7 species have a 2n number of 16, but O. gurneyi has a diploid number of 12 chromosomes, the lowest number yet reported for any species of tick. The 2 species used in this study are the only ones in the genus Ornithodoros known to be restricted to Australia.

Information about the cult of the divi and divae greatly increased with the publication of the Feriale Duranum. The editors of the latter have shown that the divi and divae whose cult the Army took over were those of the fasti publici. The divae included Trajan's sister Marciana and her daughter Matidia but no member of the Julio-Claudian and Flavian families.

SYNOPSIS. Parthenogenesis is discussed according to type (arrhenotoky, thelytoky, deuteroLoky, artificial parthenogenesis, gynogenesis) and presence in various acarine taxa. Evidence for parthenogenesis is based on rearing and/or cytological studies. Arrhenotoky occurs in Mesostigmata, Prostigmata and Astigmata and usually does not occur sporadically throughout these taxa; when present it operates in many closely related species as the major type of reproduction in certain genera, subfamilies or families. Thelytoky is present in Mesostigmata, Metastigmata, Prostigmata, Astigmata and Cryptostigmata, but in no case is the major mode of reproduction in higher taxa, i.e. subfamilies, families. Its sporadic occurrence may or may not be accompanied by polyploidy. Deuterotoky occurs in one acarine group (Listrophoridae) and artificial parthenogenesis is possible in ticks (Metastigmata). Gynogenesis is present in several species of haplo-diploid Mesostigmata (some Dermanyssidae, Phytoseiidae), although it is usually considered in connection with thelytoky. Current studies of the effects of ploidy level on morphological variation indicate greater character variability in diploid females than in haploid males. In some species of ticks thelytoky is expressed differentially even on an intraspecific level. One geographic strain of a species may have the ability to reproduce thelytokously, but if mated produces males and females.