The description and designation of a neotype, Plastobelyta gallicola Kieffer, and an additional distribution record of Espinosa nothofagi Gahan belonging to the subfamily Brachyscelidiphaginae (Pteromalidae: Chalcidoidea) from Chile, are discussed.

A series of constant observations on Amblyseius largoensis (Muma) on excised avocado leaves in the laboratory revealed that the hunger level of this predator directly affected the time spent feeding on individual prey, the relative aggressiveness, the frequency of successful captures, the length of digestive pause, and the speed of movement. Feeding and nonfeeding periods occurred in constantly recurring cycles. Hungry predators captured 2–4 prey in succession; after each capture a digestive pause followed, the length of which increased (up to 7–8 h) as the predator became increasingly satiated. This cycle was repeated 2–3 times in 24 h. Several thresholds appeared to be responsible for this behavior pattern.

Four new species of Bolteria Uhler are described: atricornis from New Mexico, scutata and scutellata from California, and mexicana from Mexico. Adults and male genitalia are illustrated as well as those of luteifrons Knight and arizonae Knight, and host information is given. Relationships to other species in the genus are discussed and a key is provided. Bolteria luteifrons Knight is reported from Canada.

Tobacco budworms, Heliothis virescens (F.), with inherited sterility caused by irradiation of the male parent were smaller than progeny from normal parents and developed more slowly throughout the larval and pupal periods. In the second generation the population segregated into two groups, those with normal and those with delayed development. Also, when the P1 male received 15.0 krad, 8% of the F1 larvae had more than the normal five instars. Moreover, when those F1 progeny that had only five larval instars were outcrossed to normal moths, this tendency for supernumerary molts increased nearly 3-fold. The slower development of progeny of treated moths would have to be considered in field tests made to evaluate the effect of inherited sterility on the tobacco budworm. However, with continuous release of irradiated males, the delayed development or smaller size of the progeny should not lessen the possibility that this method could successfully suppress field populations.

The genus Phorocera Robineau-Desvoidy, 1830, is shown to be holarctic, divisible into a palaearctic element, the subgenus Phorocera, with three species, and its nearctic sister-group, the subgenus Pseudotachinomyia Smith. 1917, with eight, of which four, angustiforceps, auriceps, convexa and exigua, are described as new. P. webberi Smith, the type species of Pseudotachinomyia, is removed from the synonymy of slossonae (Townsend) and longiforceps Brooks is synonymized with slossonae. Keys, descriptions and figures are provided for the adults and eggs of the eight nearctic species, and oviposition in P. webberi is described. Relationships of Pseudotachinomyia with the s.g. Phorocera and with other exoristine genera are discussed.

Forty-nine 0.1 m2 emergence traps positioned over several substrate types and a range of water depths 0.9 to 5.5 m, from 2 June to 7 September 1967, collected 979 caddisflies and 195 mayflies. The caddisfly emergence was restricted to the period 24 June −27 August, and mayfly emergence to the period 2–30 July.The sex ratio for the caddisflies showed, in almost every case, a preponderance of females and no male Neureclipsis bimaculatus (Linn.) and N. validus Walk, were collected. Most of the caddisflies showed preference for a particular depth and/or substrate type. The few caddisflies which were present both in large numbers and distributed over a fairly wide depth range indicated that there is a relationship between depth distribution (temperature) and emergence time, heat perhaps being involved both in control of rate of maturation and as a releasing agent for the actual emergence.Male Stenonema interpunctatum canadense (Walker) showed peak emergence about 5 days before the females and also outnumbered the females by about 3:1. No relationship seemed to exist between depth distribution and emergence time for any of the mayfly species. However, the emergence of one species, Caenis forcipata (McD.) may be related to weather conditions.

Seven of 17 insecticides tested as conventional aerosols were effective against a susceptible strain of house flies, Musca domeslica L., producing 90% or more mortality at a distance of 150 ft from the generator. Of the seven, three were equally effective as low-volume aerosols. Diazinon was the most effective of the conventional aerosols, and Dursban® (0,0-diethyl 0-(3,5,6-trichloro-2-pyridyl) phosphorothioate) was the most effective low-volume aerosol. However, none of the compounds was effective as a conventional or low-volume aerosol against an insecticide resistant strain of flies.

Comparative tests were made in Oregon and Idaho employing sticky traps with three synthetic pheromones of Dendroctonus pseudotsugae Hopkins, frontalin, 3-methyl-2-cyclohexen-1-one, and trans-verbenol, and the host attractants Douglas-fir resin, alpha-pinene, and camphene. The attractiveness of frontalin combined with host volatiles reported earlier from Idaho was confirmed. The combination of trans-verbenol with frontalin plus camphene in Oregon brought the highest response among synthetic treatments, but the addition of trans-verbenol to other treatments with frontalin sometimes decreased beetle response.3-Methyl-2-cyclohexen-1-one almost nullified the attractiveness of all baits tested. The practical use of such a compound to prevent beetle aggregation and protect susceptible Douglas-fir trees as well as to regulate the "spillover" from attractive baits is considered as a possible new method of protection against bark beetles.

Flash photography of the wings of a decticine katydid, Metrioptera sphagnorum (F. Walker), during stridulation, indicates that major trains of sound pulses of both song modes coincide with wing closures. The song mode characterized by intense ultrasonics is generated by tooth–scraper interactions over an interval of approximately 60 teeth at the lateral end of the file. A more medial file region is employed for the audio-dominated mode. Tooth removal confirms the role of different file regions in mode generation. Each pulse of the ultrasonic mode closure is a wave train of 10–15 waves of uniform amplitude, approximating a pure tone frequency of 33 kHz.

The identity of Leucopis (Leucopis) argenticollis Zetterstedt, an adelgid predator described from Sweden, is established and a lectotype is designated for it; L. orbitalis Malloch, described from Illinois is placed as a synonym of it. Another species (predator of the mealy plum aphid) that was formerly confused with argenticollis, is described as Leucopis (Leucopis) conciliata McAlpine and Tanasijtshuk, new species. Both species are shown to be holarctic and are treated from the standpoints of adult and larval morphology, biology, and distribution. The paper contains 33 figures.

Laboratory-bred rats and mice fed heavy doses of the poxvirus of the spruce budworm showed no ill effects and made normal weight gains as compared with controls over a period of 8 weeks, and no deaths occurred in the treated groups. Laboratory and wild mammals exposed to aerial spray in open-topped cages similarly showed no adverse effects. Population densities, fecundity, and other pertinent life history parameters of small mammals and birds were studied relative to treatment of a forest with the poxvirus for control of spruce budworm. There were no observable interactions between these small vertebrates and the virus. It is concluded that, from the standpoint of homoiothermic vertebrates, the virus is a safe insecticide.

Infectivity tests revealed that sensitivity of larvae of Archips cerasivoranus Fitch to infection by a commercial preparation of Bacillus thuringiensis Berliner depends on the physiological condition of the insects (determined by age and nutrition), and temperature, but mostly on the presence or absence of infection by the microsporidia Plisliphora sp. and Nosema cerasivoranus Thomson.

Mortality attributable to the bacillus was 90, 40, and 30% for healthy third-, fifth-, and seventh-instar larvae after 20 days, mortality reached 90% after 3, 9, and 19 days for larvae of the same ages naturally infected by microsporidia. Also, low temperatures decreased the effect of the pathogen and starvation reduced the resistance of larvae to infection.

The results obtained suggest the action of B. thuringiensis in this tortricid is to provoke generalized septicemia rather than toxemia.

Other infectivity tests made with cultures of B. thuringiensis and Bacillus cereus Frankland and Frankland confirmed these results. The action of the two bacteria was similar, both provoking septicemia in the insect. This effect was considerably increased by the presence of protozoan diseases.

Analyses of unsaturated lipids by the iodine number method showed that infection by a microsporidian or B. thuringiensis lowered considerably the energy value index. The index reached 13.0, 25.5, and 27.0 in healthy larvae of third-, fifth-, and seventh-instar, was reduced to 5.2, 17.0, and 15.0 by a microsporidian infection, and to 7.5, 18.0, and 22.5 by a B. thuringiensis infection. When an infection with both pathogens was induced, the value decreased to 4.0, 8.0, and 7.5.

Adults of Chrysolina quadrigemina (Suffr.) from Westbank, British Columbia, were compared with those from Lotus, California, for differences in behaviour, physiology, and colour in association with adaptation to the long, cold winters at the former location. It was found that the Westbank beetles tend to seek shelter more readily from freezing temperatures than do those from California. They also lay more eggs, as measured during 41/2 months of their oviposition period. Most eggs from both populations probably hatch in spring. The proportion of bronze beetles in the total population correlated with high mean and mean minimum temperatures in the coldest months of the year at 11 collection areas in France, Australia, U.S.A., and Canada.

Toxicities and teratogenic effects on Musca domestica L. of methyl and ethyl esters of fatty acids have been described. In general, esters of fatty acids containing 10 or fewer carbon atoms in the chain are toxic and melanogenic. Esters of higher members are less toxic, but melanogenic. However, esters of acids containing 13 or more carbon atoms in the chain show special interactions with insects, and methyl trans-2-tridecenoate has a teratogenic effect on the developing wing of the house fly.

Experiments were carried out to determine the functional response of Podisus modestus (Dallas) to densities of two colonial species of jack pine sawfly, Neodiprion swainei (Middleton) and N. pratti banksianae (Rohwer). Two types of functional response curve were exhibited by the pentatomids, a domed response curve and a negatively accelerated curve.The domed response was caused by the more effective defense reactions of the sawfly larvae at higher densities.An equation is proposed for the domed response curve. The implications of the domed functional response are discussed in relation to the social behavior of these sawflies.

The peak of phototactic response of Trialeurodes (Asterochitori) vaporariorum (Westw.) to equal numbers of quanta of monochromatic light in the range 475–625 mμ occurred at 540–550 mμ. and a hump of "red" sensitivity occurred near 600 mμ. This coincided with the transmission spectrum of host leaves. The response to light intensity was hyperbolic but it was linear within the variance in the range used for the action spectrum. Corrections were made for decreasing sensitivity during experiments. The absorption spectrum of a pigmented eye-preparation included a shoulder at the wavelength that caused maximal phototaxy. Work on greenhouse light traps is recommended. Preliminary colorimetric data did not support a capacity for colour vision.

The taxonomic framework of the lepidopterous family Sphingidae established by Rothschild and Jordan (1903) contains many anomalies. Indeed, it has been suggested that as the taxonomic lines run across both larval and host-plant groupings, the family should be totally rearranged. In this paper the host plants of the Semanophorinae (one subfamily of the Sphingidae) are examined and discussed. On the basis of host plants, five groups of sphingids, which appear to be taxonomic entities, are distinguished. The identification of the host-plant groups is also a preliminary to the use of Celerio euphorbiae (L.) for the biological control of weedy Euphorbia spp. in Canada.

A sequential sampling method for egg clusters of the Swaine jack pine sawfly, Neodiprion swainei Middleton, is described.

There are no valid reasons to believe that the allegedly successful biological control attempt against Cephus pygmaeus (L.) in Ontario was in fact a success. There are definite indications that it was a failure.

Two new species, Dialithus scintillons from Cerro Campana, Panama, and Dialithus festivus from Chiapas, Mexico, are described. The description of the formerly monotypic genus Dialithus Parry is slightly altered. Jeannelosis auriculatus Bourgin (1945) is considered a synonym of Pantodinus klugi Burmeister (1847).