The orientation of Aedes aegypti in an upward or downward vertical air current was studied. The vertical movements of A. aegypti which have been activated by CO2 are always against the air flow and toward the inlet end, where the insects alight and probe. With sufficient illumination A. aegypti locate an invisible artificial host whether it is at the top with air moving down or at the bottom with air moving up. They do not attempt to locate a visible, black, artificial host placed downstream. Body attitude is similar in upward or downward air flow. The mosquitoes follow the vertical movement of a surrounding spiral stripe pattern, whether stripe movement is upward or downward, whether air is still or moving vertically with or against the stripes. They will not fly against stripe movement to reach an upstream host, real or artificial. Repellent vapor destroys the upstream orientation when air flow is vertical but not when the flow is horizontal. The stripe-following action is not affected by repellent. The experiments indicate that A. aegypti possesses a vertical-air-speed sensor, of a mechanical type, to direct movement up or down in a vertical air stream. The cybernetic system must be complex and requires cooperative use of mechanical and optical sensory information channels. The initial action of repellent vapor appears to be peripheral rather than central to the nervous system, and to affect only the mechano-, chemo-, and thermo-receptors.

The apple mealybug, Phenacoccus aceris Sig., has been a pest of apple trees periodicallv since an outbreak was reported by Gilliatt in 1935. The writer investigated mortality in its population during the summer of 1966 in connection with the current sporadic outbreak in the Annapolis Valley. Decline of outbreaks was attributed bv Marshall and Pickett (1944) to attacks by the parasite Allotropa utilis (Mues.) (Hymenoptera: Platygasteridae), and the abundance of this parasite in the current upsurge in mealybugs suggests it is an important factor. Mr. K. H. Sanford (personal communication) estimated approximately 58% of the mealybugs in the winter of 1965–1966 and about 80% in the winter of 1966–1967 were parasitized by this species.

Pelecorhynchns peñai is described as new from Chile. A distinctive form, it seems to show close relationship only with P. kröberi Lindner.

This paper contains six annotated keys to the larval behavior of 28 species of Lepidoptera that mine the leaves of Picea spp., Abies spp., Tsuga canadensis (L.), Larix spp., Juniperus spp, and Thuja occidentalis L.

The use of Dry Ice (solid CO2) for immobilising adult houseflies and the use of all-glass handling and holding systems contribute to simplification of the general bioassay procedure with small control mortalities.

This paper is the first in a series on the Lepidoptera of the Sierra Madre Occidental area of Durango, Mexico. The immature stages of eight species of Geometridae are described in detail: Grossbeckia semimaculata Barnes and McDunnough, Semiothisa cyda (Druce), Galenara lallata (Hulst), Glena interpunctata interpunctata (Barnes and McDunnough), Iridopsis sp., Anacamptodes angulata Rindge, Phaeoura kirkwoodi Rindge, and Sicya snoviaria Hulst. Less detailed descriptions or short notes are given for the pierids Colias caesonia (Stoll) and Eucheira socialis Westwood; the arctiids Halisidota propinqua Henry Edwards and Arachnis perotensis Schaus; the noctuids Lichnoptera gulo Herrich-Schaeffer and Lacinipolia eucyria Dyar; a notodontid, Disphragis edwardsi Druce; a lasiocampid, Malacosoma incurvum aztecum (Neumogen); a pyralid, Dioryctria rossi Munroe; and an olethreutid, Petrova albicapitana (Busck).

Detailed descriptions and illustrations are given for the immature stages (egg, larva, prepupa, and pupa) of Stenodynerus claremontensis (Cameron), a solitary ground-nesting vespid wasp from the western United States. Special attention is given characteristics which may be used to separate the four larval instars.

Capric acid added to a food – whole wheat flour and dried brewers’ yeast – to constitute 2.5% or more of the foodstuff killed all Tribolium confusum Jacquelin du Val within 8 weeks. Lesser amounts of capric acid resulted in different degrees of mortality. By the end of 4 weeks similar results were inevitable when varied levels of capric acid were added to two representative dehydrated foods, tapioca pudding and macaroni and cheese. This uncustomary use of a long-recognized insecticidal fatty acid has some merit: for immixed with foodstuff it can control insect pests, and yet it, as a natural constituent of milk etc., is no stranger to metabolic systems of higher animals, so probably is not too hazardous to humans.

Chrysothyridia n. gen., related to Didymostoma Warren, is described, with Gonocausta invertalis Snellen as type-species. C. triangulifera n. sp., from the Philippines, type locality Mt. Makiling, Luzon, is described. Didymostoma is recognized as distinct from Bocchoris Moore and Bocchoris aurotinctalis Hampson is transferred to Didymostoma.

Six nearctic species of the genus Chionodes Hübner feeding on Acer (3), Quercus (2), and Salix (1) are dealt with. Keys to the species based on male and female genitalia are presented. Moths and genitalia are described, male and female genitalia are figured, and distribution maps are included. Two new species are described: Chionodes acerella n. sp. from British Columbia, on Acer sp.; Chionodes salicella n. sp. from British Columbia, on Salix sp.

Suspected predatory invertebrates associated with the larch sawfly, Pristiphora erichsonii (Hartig), on tamarack were confined in cages with sawfly eggs or larvae to determine which species were predaceous. Most of the insects were found to feed on larch sawfly eggs or larvae under these conditions, but very few spiders ate larch sawfly. The amount of food eaten by various predators is presented.

Seasonal population trends of the more common predators and prey available to them were determined from samples of tamarack branches taken at weekly intervals. Associations between the numbers of various predators and prey per 20-branch sample were investigated, and a number of significant predator–prey correlations were obtained. These included correlations between Deraeocoris and sawfly eggs, Plagiognathus and sawfly eggs, and Tetraphleps and sawfly eggs. However, estimates of larch sawfly egg mortality under field conditions showed that egg mortality was largely independent of egg density in the range of populations studied, and showed little relationship to predator density per 20-branch sample. This is because the distribution of larch sawfly egg predators per individual branch was random and appeared to be independent of egg density. Single factor analysis of annual egg populations and egg survival indicated that survival in the egg stage is of no value in predicting population trends of the larch sawfly.

The first record of the occurrence in North America of the white-tipped clover case-moth, Coleophora frischella L., was made in June 1966 when a single adult was taken by Heinemann on Picton Island, N.Y., in the St. Lawrence River (Freeman, personal communication). Independently, Trieselmann collected the larvae from white sweet-clover, Melilotus alba Desr., on 28 July through to 8 August 1966 at many points around Pembroke, Ont. Detailed examinations made at two of the collection points indicated that between 15 and 20% of sweetclover seeds were damaged. Because of its potential economic significance, the authors wish to make the presence of this species known to agricultural entomologists in Canada and the United States.

The life history and habits of Epinotia solandriana Linnaeus are discussed and the immature stages described. Information is given on distribution, host trees, variations in wing pattern of the adults, laboratory rearing, and parasites.

High winter mortality of eggs of three species of grasshopper occurred at various locations in Saskatchewan. Climatological factors associated with these mortalities indicated that egg survival during the winter is dependent upon snow cover as well as upon the intensity and duration of periods of subzero air temperatures.

Females of I. conquisitor could not be conditioned to attack horizontal tubes instead of vertical tubes of the same size and probably cannot distinguish between them. I. conquisitor could be conditioned to attack tubes of particular lengths or diameters and tubes mounted on pins rather than on plastic forms. These results are interpreted as showing that the parasites can recognize these differences in the host shelter and that these characteristics could influence host selection. It is suggested that if a polyphagous parasite to be introduced against a particular pest is first conditioned to that host in pieces of its host plant, the success of the parasite in finding that host and hence its chances of establishment would be increased.

The water mite Albia caerulea Marshall, 1927, is reported from Lake Opinicon, Leeds Co., Ont. Descriptions and figures of larvae and of nymphs reared from them are presented. The occurrence of this mite on caddisflies (Leptocerus americanus (Banks), Trianodes sp., and Leptocella sp.) is recorded.

Inferences regarding the value of Nasonia vitripennis in the natural control of Musca domestica based on laboratory research should consider the general absence of this parasite on that host in nature. Predominant natural parasites of M. domestica are listed.

The technique of direct shadow photography has been adapted to recording the convection currents from the human body. The resulting pictures suggest that insect repellents may be more effective if applied to the clothing than to the exposed skin only.

The Atlantic Provinces received many coleopterous immigrants from Europe during colonial times. These immigrants live in man-made habitats, and they show unnaturally restricted distributional patterns. Many were introduced independently to regions about Puget Sound, and there were multiple introductions in the East. Parthenogenesis is a factor in the establishment of imported otiorhynchine weevils. Imported species not previously reported from North America are Abax parallelopipedus (Pill. & Mitt.), Eusphalerum torquatum (Marsh.), Meligethes viridescens (Fab.), and Longitarsus luridus (Scop.). Aphodius tenellus Say is strictly North American and has been confused with the Eurasian species that should be known as uliginosus Hardy. American records of Sitona tibialis (Hbst.) and probably those of S. discoideus Gyll. are based on S. scissifrons Say, which is native to North America. The Alaskan Philostratus ptinoides (Germ.) occurs, evidently as an import, in eastern Canada. New synonymy is proposed: Thes bergrothi (Reitter, 1880) = Enicmus tricarinatus Brown, 1934; Aphodius borealis Gyllenhal, 1827 = A. errans Brown, 1930. Notes are given on the distribution, characters, or nomenclature of other species.

Crinophleba rostrata, a new genus and species of a phorid fly from New Brunswick, Canada, is described.