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Robert Traub, ONE of the most accomplished and respected medical entomologists of this or any generation, died on 21 December 1996 at the National Naval Medical Center in Bethesda, MD, after an extended illness. Although he is best known for his encyclopedic knowledge of fleas, his name stands for much more. He leaves a legacy of pioneering research accomplishments in several disciplines, especially flea systematics, chigger taxonomy, and the epidemiology of both scrub typhus and murine typhus. Because Dr. Traub was instrumental in founding the Journal of Medical Entomology in 1964 in which several of his substantial manuscripts were published, it is appropriate to present his obituary here and to dedicate this issue of the journal to him.

The authors present an introductory overview of the principal groups of ectoparasites (flukes, leeches, crustaceans, insects, arachnids, lampreys and vampire bats) associated with domestic animals. Currently-accepted higher-level classifications are outlined for these parasites. Almost all significant ectoparasites of domestic animals are invertebrates, the majority being arthropods (crustaceans, insects and arachnids). Some of these ectoparasites are of particular importance as vectors of pathogens. Many ectoparasite species are host-specific, and vector species typically transmit characteristic pathogens.

Approximately 250 isolates of a newly recognized virus, related to western equine encephalitis virus (family Togaviridae, genus Alphavirus), were obtained from cimicid bugs, Oeciacus vicarius; Cliff Swallows, Hirundo pyrrhonata; and House Sparrows, Passer domesticus in a study area in west-central Oklahoma at Buggy Creek and Caddo Canyons. Antigenicity of the virus strains varied slightly from isolate to isolate. This paper summarizes the ecology of the area by describing in general the flora and fauna there.

Eight species of small mammals were evaluated as potential hosts for American dog ticks, Dermacentor variabilis (Say), in an upland, tallgrass prairie study site in central Oklahoma. Only hispid cotton rats, Sigmodon hispidus, and deer mice, Peromyscus maniculatus, were found to be important hosts for immature D. variabilis. Although D. varibilis larvae and nymphs frequently infested both cotton rats and deer mice, cotton rats were the most important host species for both immature stages in the study area. Cotton rats constituted 63.2% of the total 530 small mammals captured and were hosts to 85.2% of all larvae and 88.7% of all nymphs. Deer mice accounted for 19.8% of all small mammals captured and were hosts for 14.5% of the larvae and 10.8% of the nymphs recovered. The remaining small mammal species were hosts for less than 1% of the immature ticks collected. Larval infestations peaked during summer, whereas summer and spring peaks were noted for the nymphal infestations. The relative importance of cotton rats and deer mice as hosts for immature ticks could be largely, but not completely, explained by cotton rats being more than three times as abundant as deer mice. Attachment site data indicated that differences in grooming behavior also might be partially responsible for the larger infestations observed on cotton rats. Other possible ecological and behavioral explanations of the heavy infestations observed on cotton rats are discussed.

The larva and nymph of Ixodes (Pholeoixodes) baergi Cooley & Kohls are described for the first time. This tick has been collected only in the United States on cliff swallows, Hirundo pyrrhonota, in their nests, or in adjacent habitats. To date, it has been reported from Arkansas, Colorado, Illinois, Oklahoma, and Texas. Brief notes on the synchronization of the life cycle of I. baergi with that of its host are included.

Hispid cotton rats (Sigmodon hispidus Say and Ord) were susceptible to infection with Rickettsia rickettsii Wolbach under laboratory conditions and were capable of serving as sources for infecting ticks with rickettsiae. Cotton rats developed rickettsemias that could be detected for as long as 6 h following intraperitoneal inoculation of 10(5) plaque-forming units (PFUs) of R. rickettsii (Morgan strain). An estimate of the median infectious dose (ID50) was made by inoculating six groups (eight animals per group) with serial dilutions of 10(1) to 10(6) PFUs. In this experiment, cotton rats became infected after exposure to relatively few organisms (ID50 = 37 PFUs). None of the 48 cotton rats succumbed to infection, and only 6 of the 48 rats failed to seroconvert. Dermacentor variabilis (Say) larvae were fed on rickettsemic cotton rats to determine whether this species could serve as a source for infecting ticks with R. rickettsii. A small percentage (0.9-3.0%) of larval ticks that fed on three of the four cotton rats had R. rickettsii in their tissues when examined as nymphs. A fourth cotton rat died 7 d after inoculation with R. rickettsii and infected a much higher percentage of ticks (64.0%) than the other three animals.

Summary 1. Quantitative methods of study were used in an attempt to observe the changes which took place within infected mites (Bdellonyssus bacoti) after prolonged periods of starvation and after feeding on various types of hosts. 2. The tropical rat mite was shown capable of retaining an infection of Bact. tularense from the protonymph stage throughout the subsequent stages of a single generation. In certain instances this mite transmitted the infection to the next generation. 3. The infection was also retained after several feedings on recovered mice without reduction of the number of infectious organisms. 4. Even after prolonged periods of fasting, no significant decrease in the number of organisms per mite was noted. 5. The tropical rat mite was unable to produce an infection in normal mice by biting. Infection resulted when the mites were crushed orally by the mice. 6. The LD50 titration indicated no loss of virulence in the Sm strain of Bacterium tularense upon mite passage, nor was any increase in virulence noted.

The annual business meeting of the American Grassland Council was held in Washington, D. C. on December 20, 1962. The present officers were re-e1ected to serve through 1963. Six new members were elected to the Board of Directors. Legal steps were completed during the year for incorporation of the Council.

An event of world-wide entomological interest was the 11th International Congress of Entomology held in Vienna, Austria, August 17–25, 1960. This Congress brought together some 1600 entomologists from 56 countries, thus comprising the largest gathering of entomologists held to date. The Entomological Society of America through its official and unofficial delegates was represented by approximately 200 members. The present report reviews the historical background of the Congresses, the setting of the XIth Congress and the subject matter included in the program.

Fifty-one species and subspecies of fleas are currently known in Alaska; 37 species normally occur on mammals, and 14 are associated with birds. With the possible exception of one or two species, none are restricted to the political entity, Alaska. From a study of geography, paleozoology, morphology and taxonomy, the fleas of Alaskan mammals are reported to be derived from three principal faunas. The largest group apparently arose from Eurasia as the mammals migrated across the Bering Land Bridge during the glacial periods of the Pleistocene epoch and earlier. A study of host associations reveals that distribution of the fleas is not concordant with that of the preferred hosts. For example, of six species associated with microtine rodents in the taiga, only two have followed the same hosts into the vast tundra region to the north. Fleas originally thought to be restricted to the Arctic regions are now known to have adapted to hosts within the taiga, albeit the distribution is not an extensive one. These distribution patterns indicate that the Siphonaptera are subject to ecological factors and pressures over and above those which affect the distribution of the mammals and birds upon which they depend for their existence.The data collected thus far indicate that most fleas in the taiga have one, or possibly two, generations a year.

Feeding habits of mosquitoes of the taiga and tundra were studied. Greater emphasis was given to those of the taiga, however, because of the longer mosquito season and the greater variety of genera and species present. A tower was built with platforms at 6-foot intervals up to 42 feet, to study vertical distribution and host preference. Domestic chickens, white laboratory rabbits and varying hares, along with empty control boxes, were placed at the various heights. Approximately 80% of the 10,722 specimens obtained were collected in the first 18 feet. Using insect nets, 46,123 specimens were collected in the vicinity of the tower, both from vegetation and aerially up to height of 6 feet. Only six showed evidence of a recent blood meal. Evidence indicates that most subarctic mosquitoes take but one blood meal, a fact of considerable importance when considering them as vectors of zoonoses. Studies of the natural history of Culiseta alaskaensis indicated that the unfed adult females overwinter close to the ground in dense growths of grass underneath the snow cover where the temperature range is from 16 - 20 F. in the laboratory, C. alaskaensis lived only about one week at 0 F. Chromatographic studies did not reveal the presence of glycerol compounds in the hemolymph.

A study of the role of the Eastern Phoebe ( Sayornis phoebe ) as a secondary host for Ornithodoros concanensis was undertaken as part of a long-term study on ectoparasites of the Cliff Swallow ( Petrochelidon pyrrhonota ). A total of 1575 O. concanensis were removed from 11 phoebe nests and nestlings. Despite probable long-term cohabitation of the cliff-face habitat, Eastern Phoebe nestlings have not adjusted to the association with O. concanensis as successfully as have Cliff Swallow nestlings.

Our national meetings should be provocative and educational. The information provided does not necessarily need to be harmonious with our point of view. Frequently a “burr under the saddle blanket” can do more good than an unlimited amount of partisan praise ! Hopefully, this year we can encourage many interdisciplinary features by the various Section Chairmen. Not the least important from this standpoint should be the workshops and/or informal discussion period. The informal discussion period can add much to our program. It creates an excellent opportunity for the young researcher to exchange his views with established individuals in a particular field. Hopefully, we can have announcements about the workshops and/or informal discussion periods so that the individuals will have an indication as to what will be available and that they can have their thoughts reasonably well prepared before coming to the meeting. Hopefully if one is to participate in an informal discussion, the institution represented would consider it equivalent to reading a paper and therefore pay all or a part of the expenses involved.