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Seventeen species of Coleoptera, Lepidoptera, Diptera, and Hymenoptera showed chemical differences by the method of paper chromatography in an evaluation of the method for taxonomic purposes. The analyses were complicated by pattern differences evident in larval, pupal, and adult stages of some species. Geographic isolates of Malacosoma disstria Hbn. as well as of Chamaepsila rosae (F.) and physiological entities within Pristiphora erichsonii (Htg.) show identical patterns; however, differences are found at specific levels. Paper chromatography is therefore a valuable taxonomic tool, especially as the technique is capable of considerable refinement.

A new ultramicromethod for the quantitative estimation of amino acids by paper partition chromatography is described. The material required and the procedure adopted are detailed. As an application of this new method, a quantitative estimation of the free amino acids present in the blood of the last larval instar of Galleria mellonella (L.) is presented. The results obtained, when converted into total amino nitrogen, compare favorably with total amino nitrogen results already published in the literature.

Reproducible live wet weights may be obtained for medium to large larvae of Metriocnemus knabi and Chironomus attenuatus after blotting them on filter paper for 1 min. To obtain reliable measures of wet weight for smaller larvae the blotting time must be reduced in proportion to the surface area/volume ratio of the larvae. Dry weights are easily obtained by oven drying at 60 °C for 24 h but drying for several days does not affect the results. A temperature of 100 °C decreases die percentage dry matter in C. attenuatus. Both species display an increase in percentage dry matter with increasing size. The extent to which the gut is filled with food has no effect on the percentage dry matter. Attempts to determine dry weight directly from preserved larvae were unsuccessful.

An extract of each of Aedes aegypti (L.), A. atropalpus (Coq.), and Culex pipiens (L.) was shown by paper chromatography to contain 12 ninhydrin-staining peptides. None of these peptides from the A. aegypti extract was capable of eliciting skin reactions in a volunteer sensitive to A. aegypti bites. A reaction equivalent to that caused by a mosquito bite was produced by an estimated 10−3 g of dialyzed A. aegypti extract from which the ninhydrin-staining peptides had been removed. Of the solvents tested in attempting to fractionate this active material, the most suitable was 65% acetone. By this means, A. aegypti extract was shown to contain at least four fractions capable of producing skin reactions in volunteers sensitive to A. aegypti bites.

Olfaction is the principal sensory modality through which insects locate their food sources, mates, and oviposition sites. Insects offer certain advantages as experimental models for the study of mechanisms of olfaction, and a thorough knowledge of the antennal olfactory sensory cells is essential for such studies. While the sphinx moth, Manduca sexta, has proved to be an especially favorable experimental model in studies of pheromone processing in males, little is known about the female olfactory system, including the antennal olfactory sensilla. In this and another paper in this series, we present the first thorough investigation of the structure, innervation, number, and distribution of sensilla on the antennal flagellum of female M. sexta. The flagellum of the female moth bears eight morphological types of sensilla: two trichoid, two basiconic, one auriculate, two coeloconic, and one styliform complex. In this paper, we describe the two types of trichoid and two types of basiconic sensilla. The first type of trichoid sensillum, a long hairlike sensillum averaging 34 µm in length, is innervated by two bipolar sensory cells, and the second type, a shorter hairlike sensillum averaging 26 µm in length, is innervated by either one or three bipolar sensory cells. The first type of basiconic sensillum is a long peg, averaging 22 µm in length, and the second is a shorter peg, averaging 15 µm in length. Both types of basiconic sensilla are innervated by three bipolar sensory cells. These trichoid and basiconic sensilla have structural features characteristic of insect olfactory sensilla.

The parasitoid Aphidius nigripes spent more time searching on potato plants previously infested with aphids than on fresh plants, suggesting the presence of searching stimulants on infested plants. Water extracts of aphid honeydew applied to the surface of foliage or to filter paper discs increased searching time and affected the locomotory behavior of parasitoids. When crossing a honeydew-treated area on filter paper, female parasitoids exhibited arrestment, antennal examination, abdominal protraction, reduced walking speed, and increased turning. Upon losing contact with honeydew-contaminated substrate, parasitoids often exhibited a klinotactic response which drove them back to the treated area. The time spent by individual parasitoids within a honeydew-treated area on filter paper decreased with successive visits, but the initial response level was restored when the insect was prevented from contacting honeydew for 1 h. The retention response exhibited by parasitoids contacting a honeydew-treated area increased with honeydew concentration, but levelled off at high concentrations. Naive parasitoids were more responsive to the retention effect of honeydew than experienced individuals.

In Part I of this paper consideration was given to the role of climate in the initiation of outbreaks of the spruce budworm in New Brunswick. Analysis of the available weather data showed that the 1912 and 1949 outbreaks developed after several consecutive dry summers. Support was given to the theory of climatic release, which explains the time and place of outbreaks on a climatic basis. However, the recorded history of the spruce budworm also shows that high populations appeared in New Brunswick shortly after "spreading" through Quebec, and this suggests that the New Brunswick outbreaks are also a continuation of this spread. In the present part of the paper consideration is given to the role of dispersal. Moth dispersal is a more effective agent of spread than larval dispersal. Moths may be transported by convectional and turbulent air currents for long distances. Light traps used to detect the incidence of moth movements, showed that large segments of a population may be transferred from one area to another. Unspent females often predominate in these movements. Moth invasion was not detected before the 1949 outbreak although there is evidence from other sources that it occurred in 1948. When deposited in dense, mature, softwood stands, the moths can create outbreaks, but when deposited in young, open, or mixed-wood stands the ensuing high populations soon decline unless bolstered by repeated invasions. Populations in New Brunswick showed gradual and general increases as early as 1947. It is thought probable that these increases resulted from the build-up of local populations through climatic release. The nearest highly-populated centers were over 100 miles to the west in 1947. Later, invasion of moths from centers outside of the Province may have hastened the process.

The influence of a temperature default on ribosomal RNA (rRNA) secondary structure models was studied with the "Mfold" energy-optimization program. Folding models of the internal transcribed spacer (ITS) 1 rRNA for both Drosophila simulans (Insecta) and Isabellaria adriani (Gastropoda) were generated at two different temperatures. The folding models are compared with the models previously shown for the ITS-1 of D. melanogaster Oregon R strain and I. adriani. A search for phylogenetically informative ITS-1 folding motifs was conducted for D. simulans. In I. adriani, a new approach for ITS-1 secondary structure analyses is suggested. The paper also elucidates results inferred from three energy-optimizing programs (Mfold, GeneBee, and STAR). These three folding programs give different information on the structure and free energy of a ITS-1 rRNA molecule. Furthermore, secondary-structure models of the small subunit (ssu) rRNA of Daphnia pulex (Crustacea: Cladocera) were investigated. The ssu rRNA molecule is usually folded according to alignment information. Here, ssu folding patterns are computed with Mfold using two temperature conditions. The two Mfold models are compared with the alignment model previously suggested for D. pulex. Three cladoceran-specific motifs and a short stem motif within the ssu rRNA of eukaryotes are discussed with respect to structure and phylogenetic information.

The antennal flagellum of the female sphinx moth, Manduca sexta, bears eight types of sensilla: two trichoid, two basiconic, one auriculate, two coeloconic, and one styliform complex. We previously described the fine structure of the trichoid and basiconic sensilla (Shields and Hildebrand 1999). In this paper, we describe one type of auriculate, two types of coeloconic, and one type of styliform complex sensilla. The auriculate (ear- or spoon-shaped) sensillum is a small peg that averages 4 µm in length, is innervated by two bipolar sensory cells, and has structural features characteristic of an insect olfactory sensillum. Each of the two types of coeloconic sensilla is a small peg that averages 2 µm in length and is recessed in a cuticular pit. One type of coeloconic sensillum is innervated by five bipolar sensory cells and has structural features characteristic of an insect olfactory sensillum or olfactory-thermosensillum, while the other is innervated by three bipolar sensory cells and has structural features characteristic of an insect thermo-hygrosensillum. The styliform complex sensillum is a large peg that averages 38-40 µm in length and is formed by several contiguous sensilla, the number of which depends on the location of the peg on the flagellum. Each unit of the styliform complex sensillum is innervated by three bipolar sensory cells and has structural features characteristic of a thermo-hygrosensillum. We also ascertained the number and distribution of each of the eight types of sensilla on a single flagellomere (annulus) about midway along the flagellum of a female antenna. A total of 2216 sensilla were found on the dorsal, ventral, and leading surfaces of that annulus.

This paper relates a female age effect to the mating behavior of Chryseida bennetti Burks, an ectoparasitoid of the bean weevil (Acanthoscelides obtectus (Say)). The sexual behavior includes rapid courtship and copulation followed by a postmating courtship behavior ("guarding"). Male guarding behavior varies according to the females' age, with males guarding females of 2–3 days old longer than younger and older females. A period of sexual maturation is necessary for most of the males. Females' attractiveness begins at the pupal stage, and their receptivity on emergence. Mated females are still attractive to males. Multiple matings (up to four copulations) with the same male have been observed. The females' age seems to control copulation frequency and the duration of the postmating courtship behavior. Two- and three-day-old females had more successive multiple matings with the same male than the other females did, and males spent much more time guarding them. The age of the males (except from newly emerged males) did not seem to influence copulation frequency. On the other hand, the complexity of the sequential courtship behavior increased with the age of the partners. The function of males' postmating courtship is discussed.

This paper surveys the biology of central Amazonian fishes and the physicochemical conditions of their habitats, with particular emphasis on factors related to respiration, in order to place in an ecological perspective the studies of respiratory physiology carried out on the 1976 Alpha Helix Amazon Expedition.The environment is strongly influenced by the annual flood cycle and is characterized by high temperatures and widespread hypoxia. Important differences exist among habitats in the absolute levels and degree of dairy and seasonal variation in temperature and oxygen supply.Air-breathing fishes are numerous and diverse in comparison with other types of aquatic environment, but make up only a small proportion of the total fauna, even in the more hypoxic habitats. Many other species use the oxygenated surface layers for branchial respiration. The potential interrelationships between respiratory strategies and other aspects of the species biology such as feeding niche, habitat type, aniipredator strategies, and capability of overland movement s are discussed.

The parasitoid wasp Trichogramma minutum Riley (Hymenoptera: Chalcidoidea: Trichogrammatidae) adjusts its progeny allocation to the exposed volume of its insect egg host. This paper deals with the mechanism for this size discrimination, which is not dependent upon chemical or visual cues or repeated parasitism. The wasps are also able to discriminate between hosts of the same diameter that differ in exposed surface area, and do not use curvature to determine progeny allocation under these conditions. A computer-based event recorder was used to collect information about the host-examining behaviour of the wasp. Of the examining-path parameters that change with surface area, only the duration of the wasp's initial transit across the exposed surface of the host correlated significantly with the number of eggs subsequently laid by the wasp. Artificially reducing the initial transit of the wasp by obstructing its path resulted in significantly fewer eggs per host. Both large and small wasps allocate the same number of progeny to hosts of the same exposed volume, and take the same time to complete their initial transits. We propose that Trichogramma use the absolute length of their initial transit, measured as the transit's duration, to set clutch size to absolute exposed host volume. This behaviour allows Trichogramma to lay the number of eggs into each host that ensures maximum reproductive success, regardless of the wasp's own dimensions.

The cyphonautes larva of Membranipora membranacea (phylum Bryozoa, order Cheilostomata) is a laterally compressed, planktotrophic larva covered by a triangular, bivalved shell. In this paper, the general morphology of the larva and the cytology of the body wall and gut are examined by light and electron microscopy. The outer part of the body wall underlying the shell consists of an essentially nonciliated layer, called the aboral epithelium. At the larval apex, the aboral epithelium forms a knob-shaped apical organ. The apical organ contains putative sensory cells, a basal nerve plexus, and a group of undifferentiated epithelial cells that probably corresponds to a blastema. The body wall at the base of the larva constitutes the larval locomotory organ or corona. The corona consists of two rows of multiciliated cells, which are flanked by myoepithelial cells and monociliated cells. A large mantle cavity, referred to as the vestibule, occupies the central region of the larva. The vestibule is partially divided into an anterior inhalant chamber and a posterior exhalant chamber by two ciliary ridges that run along the sides of the mantle cavity. At the base of the larva, the inhalant chamber is surrounded by a horseshoe-shaped flap of tissue, called the velum. Apically, the inhalant chamber forms a densely ciliated preoral funnel. Food particles filtered by the ciliary ridges are conveyed to the larval mouth by cilia in the preoral funnel. The mouth in turn leads into a tripartite gut consisting of an esophagus, stomach, and intestine. Two types of ciliated lining cells occur in the esophagus and stomach. The intestine appears to be lined by nonciliated epithelial cells and empties into the exhalant chamber by way of an anus. Morphological features of the cyphonautes larva are compared with those described for other bryozoan larvae in an attempt to define homologous structures among the various larvae of bryozoans.

This paper summarizes factors regulating seasonal emergence of Dolania americana in the Blackwater River, Florida, U.S.A. Emergence is temperature-dependent, and emergence on a given day can be predicted from the period of nymphal maturation and the pattern of temperatures on previous mornings. Development of the last two nymphal instars follows a pattern that can be interpreted linearly or by day-degree summations. Increases in water temperature at time of emergence (dawn) on the previous day provide the best correlation with emergence. Different responses to temperature events that cue emergence probably result from the effects of different temperature regimes in which the different populations develop. In experiments, males emerged equally 1 and 2 days after increases in the daily low water temperature, while females emerged more frequently after 2 days of increasing temperatures.

The amino acids of new and old foliage of flowering and non-flowering balsam fir (Abies balsamea (L.) Mill.) and white spruce (Picea glauca (Moench) Voss) were investigated using two-dimensional descending paper chromatography. The data were analyzed for variation associated with age of foliage, age of tree, and flowering condition. The concentration of foliar amino acids was greater in balsam fir than in white spruce, and greater in new foliage than old foliage.The difference in concentration between foliage of flowering and non-flowering trees was smaller. However, the new foliage of flowering fir had higher levels of most of the amino acids examined than any other foliage category. This appears to reflect the known suitability of these foliage categories for spruce budworm larvae. While the data presented do not quantify the ecological significance of this apparent correlation, they do support the theory that variations in the nutritional quality of host plants play a very important role in the dynamics of herbivore populations.

This paper describes a bacteriological study of strains of Bacillus cereus Frankland and Frankland producing disease in codling moth larvae and an investigation of their pathogenicity. Strains of the bacterium were pathogenic to the codling moth by feeding or by injection.

This paper describes the use of the serological procedure known as the precipitin test to study the rate of digestion of host blood in mosquitoes. In the laboratory, at constant temperatures, precipitin reactions were obtained on blood meals of Aedes aegypti eight days after engorgement when the mosquitoes were held at 11 °C. but only one or two days after engorgement when the holding temperature was 27 °C. Field studies with A. hexodontus in northern Manitoba also showed that temperature has a strong influence on the rate of blood digestion. Pertinent literature is reviewed and the limitations of the precipitin test are discussed. Until now little attention has been devoted in Canada to possible disease transmission by mosquitoes. Increasing interest in mosquitoes as vectors of the encephalitides and proved transmission of western equine encephalitis by Culex restuans in Manitoba suggest the importance of further knowledge of mosquito physiology.

The various tissues of two species of insects, one cold-hardy and the other not, were found to have melting points between −0.5° and −1.0° C. Because of this uniformity, the relationship between temperature and extent of ice formation, quantitatively worked out for blood of Loxoslege sliclicalis (L.) in a previous paper, may be considered representative of insect tissues in general, except possibly those of insects that withstand freezing.

Samples of nine crystalline mustard oil glucosides including sinigrin were isolated from plant tissues of species in the families Cruciferae and Tropaeolaceae. The isolations were achieved by the use of column chromatography on neutral alumina, cellulose powder, activated carbon; by paper and thin-layer chromatography; and by crystallization from methanol–water mixtures.Feeding responses of fifth instar larvae of Plutella maculipennis (Curtis) were tested on agar–cellulose diets containing individual glucosides at various concentrations in the presence or absence of 0.1 M glucose. The amount of feeding was measured by counts of frass pellets produced by the larvae during the test period. All the above-mentioned glucosides were found to act as feeding stimulants for the larvae of P. maculipennis. However, the relative palatability of these glucosides at the same concentration (20 mg per 10 ml of water in the diet) was found to be in the following order: progoitrin > glucocheirolin = glucoconringiin = glucoerucin > glucotropaeolin = sinigrin = sinalbin > gluconasturtiin = gluconapin. Higher concentrations of the glucosides, gluconasturtiin, and gluconapin were toxic to the larvae.