In adult virgin females of the sugar beet wireworm, Limonius californicus (Mannerheim), the sex attractant (recently identified as valeric acid) is found primarily in the fifth and sixth abdominal segments. Ether extracts of virgin females and of females that had been mated for not more than 4 hours prior to death contained the highest concentration of the attractant. The concentration of attractant in mated females decreased as the post-copulatory interval increased. In the laboratory maximum sexual response was elicited from males exposed to as little as 0.008 female equivalent of attractant. Numerous thin-walled sensoria are present on the eight distal segments of the male antennae and apparently function as chemoreceptors. Response of males to the attractant was not affected by bilateral amputation of the five distal segments, decreased progressively with the amputation of segments 6 and 7, and was eliminated upon removal of segment 8. Males of L. californicus responded only to extracts of females of that species whereas males of Limonius canus (LeConte) responded to extracts of females of both species.

This study includes the first published record of a berothid life history and the first description of a second instar larva. The incubation period was 7 days (N = 21), and the median durations of the first and third stages were 12.5 days (N = 8) and 20.8 days (N = 5). The length of the second stadium was 3 days (N = 5). One adult emerged, after being within the cocoon for 20 days (all temperatures, 75±3°F).

Eggs were laid in a stalked cluster in which there were fewer stalks than eggs. The first and third instars, which have piercing–sucking type mouthparts, were carnivorous and fed on the termite Zootermopsis angusticollis. Both of these stages were very mobile. On the other hand, the second instar, apparently a non-feeding stage, hung downward by the abdominal tip. It was not active except when disturbed, whereupon the body snapped into a straight position and then back again into the original C-shaped attitude. The cocoon was oval and transparent.

Viability decreased with successive instars and it is possible that the prey offered to the immatures was an inappropriate termite species and therefore a suboptimum food source. It is also likely that unfavorable physical conditions contributed to the high mortality of the immatures.

Both the second and third instar larvae are described, and the third instar is compared with a previously described third instar larva of an undetermined species within the same genus.

Two species of Chrotogonus have recently been described by Steinmann (1965) from northeastern China, and two from Kazakhstan. Only one of these, Ch. armatus, from Peking district, is valid. Ch. changi is synonymous with it; Ch. skopini and Ch. russicus are synonyms of Ch. turanicus.

One parasitic dipterous species and 27 parasitic hymenopterous species were collected. Parasites were primarily collected by mass-rearing host larvae on cut host plant foliage in the laboratory or by rearing larvae on artificial diet. The tachinid Nemorilla pyste (Walk.) and five hymenopterous species, Glypta n. sp. (Ichneumonidae), Campoplex sp. (Ichneumonidae), Agathis acrobasidis (Cushman) (Braconidae), Elasmus atratus How. (Eulophidae), and Catolaccus aeneoviridis Girault (Pteromalidae), were definite parasites, and biological notes are given. Collection data are also given for the other 22 species.

One reduviid predator, Zelus socius Uhler, and six spiders were observed feeding on C. houstonana.

First- and second-instar tent caterpillar larvae are acceptable prey for many native species of ants. The amount of predation which occurs is normally related to ambient temperature. A warm period in early spring allows ants to forage actively and often leads to destruction of the caterpillar colonies whereas a cool spring curtails ant activity and allows the caterpillars to develop beyond the vulnerable period free from predation by ants. In latter instars the caterpillars are protected completely against ants by their dense setae.

The habits of the San José scale, Aspidiotus perniciosus Comstock, and the European fruit scale, A. ostreaeformis Curtis, on harvested apples in British Columbia are discussed under the following topics: stages found on apples; distribution and mortality on apples; influence on size, odor, and skin of apples; discoloration of fruit; and appearance of scales on apples. Outstanding characteristics of the San José scale are: all stages occur on the fruit; crawlers settle primarily in the stem end of Newtown and Winesap apples, equally in the stem and calyx ends of Rome Beauty, and predominantly in the calyx end of Delicious; the scale survives longer in the stem end than in the calyx end of stored Newtown, Winesap, and Delicious apples; all scales eventually die in storage; and infestations decrease the size of apples, adversely affect color and maturity, impart a moldy odor to the fruit, and mark the skin of all varieties by causing red spots around the scales. Comparable habits of the European fruit scale are: males and females do not occur on the fruit; more crawlers settle in the stem end of Newtown, McIntosh, and Hyslop crab apples than in the calyx end but the reverse distribution occurs on Rome Beauty; the scale survives longer in the calyx end of all varieties; all scales do not die on apples placed in storage; infestations apparently do not affect size, color, maturity, and odor of fruit; and feeding of the scale seldom marks the skin of Newtown apples but it does cause purplish-red spots around the scales of all other varieties of apples.

The microtopography of a small area of tamarack bog was examined in detail and related to the distribution of cocoons of the larch sawfly Pristiphora erichsonii (Hartig). The relief of the ground surface under tree crowns was very similar to the surface not under crowns, although the whole profile was slightly higher. Cocoons were found down to the limnic peat, corresponding to the level of the lowest depressions, with the greatest numbers per unit area in the hummocks.

The microtopographies in six tamarack bogs were sampled systematically and related to water levels, and an expression combining these two factors was related to larch sawfly survival. The microtopography in each bog did not change appreciably over a period of several years, but differences between bogs were pronounced and had a marked influence on the degree of flooding caused by equal changes in water tables. Excessive moisture during the period 1955–1966 was the prevalent condition in most of the bogs and extreme drought occurred only in 1961. There appeared to be a linear relationship between sawfly survival and an expression rating the favorableness of the cocoon environment in relation to excess moisture, but four divergent observations occurred among the data for 32 plot-years. It was postulated that these divergences were due to high mortality caused by a factor other than excess moisture.

Swarming of 16 species (three genera) of Lonchaeidae is reported for the first time, and is related to the occurrence, nature, and evolutionary significance of insect swarming in general. The theory that aerial swarming is basic to the two-winged condition in Diptera is proposed. Evidence is presented to show that various swarming habits and associated morphological adaptations are primitive features of not only the Lonchaeidae, but of all Diptera. Four new species of Lonchaea from Ontario are described.

The genus Paranthrene Hübner was thought to be represented in Japan by four species, ferale (Leech), pernix (Leech), regale (Butler), and purpurea Yano, but study of the larvae suggest that regale (= yezonica Matsumura) and purpurea are in the genus Nokona Matsumura and pernix is near or in Vitacea Engelhardt. The larvae of ferale Leech have not been examined. Nokona is raised from subgeneric status.

Choristoneura houstonana (Grote) lays eggs singly in July. Egg development ranged from 8 to 11 days, with the majority hatching 10 days after oviposition.

Larvae are solitary, and mine during early instars but later instars feed externally on leaves in shelters made by webbing foliage together. There is one generation each year and overwintering occurs in a hibernaculum, in mined leaves. Field-collected head-capsule width frequencies indicated nine larval instars. Rearing larvae on seedling junipers indoors indicated a range of 8–11 instars.

Pupation occurs during June and July in the shelter where the larva feeds. The pupal stage lasted about 10 days at a constant temperature of 80°F.

The following oils were evaluated for control of the pear psylla, Psylla pyricola Foerster, phytotoxicity, and persistence on Bartlett pear trees; Orchex 696, Orchex 796 with 0.46% emulsifier, Orchex 796 with 1% emulsifier, PGSO-1, PGSO-2, and Volck Supreme. The oils were applied at the rate of 5 gal per acre in a three-spray program, one at the delayed dormant period and two during the summer.

Orchex 796 (1% emulsifier) and Volck Superme oil gave the best control of pear psylla, PGSO-1 and PGSO-2 were intermediate, and Orchex 696 and Orchex 796 (0.46% emulsifier) were the least effective. Each of the oils gave excellent control of the European red mite, Panonychus ulmi (Koch).

The oils caused enlargement and corkiness of the bark lenticels on 1-, 2-, and 3-year old wood. The pear fruits showed darker green lenticels than unsprayed fruit, but this green spotting did not persist when the pears were ripened.

Analysis showed each oil to be persistent upon pear foliage. There was little loss after 8 days and an average of 28% loss after 25 days.

Footnotes in the larval revision of the North American Aegeriidae (MacKay 1968) indicate that additional material of Cissuvora ampelopsis Engelhardt and [Carmenta] phoradendri Engelhardt was received too late for incorporation in the study. The material consists of a prepupal larva associated with an adult that is posifively identified as Cissuvora ampelopsis and two last-instar larvae believed to be phoradendri, and is discussed in this paper. The study of the material indicates that the unique larva referred to in the 1968 work as “probably Cissuvora ampelopsis” is of an unidentified genus and species, and that the species phoradendri is in Synanthedon rather than in Genus I of the Carmenta group. The larva of the true ampelopsis is described and illustrated here and the characters that key the larvae of phoradendri to Synanthedon are listed.

Two species of ants, Formica obscuripes Forel and Dolichoderus (Hypoclinea) taschenbergi (Mayr), attended species of Cinara, mainly C. gracilis (Wilson) on Pinus banksiana Lamb., in the Sandilands Forest Reserve, Man. The aphids occurred only on trees near ant hills. Removing the aphids by spraying had no serious effect on the ants. Destruction of an ant colony was followed by the disappearance of the aphids. The trees benefited through removal of defoliating insects by the ants.

A machine is described which generates a standard, mosquito-attracting “target” to which controlled additions of various volatile chemicals can be made and the amount needed to repel the insects thereby measured in micromoles per liter of air. The apparatus can be used with both solids and liquids as well as with blends or mixtures. While principally intended for testing mosquito repellents, it can probably be adapted for use with other biting insects and ticks.

The responses of adult Aedes aegypti L. to real and simulated linear movement at inanimate target areas were investigated. The results suggested that warmth and humidity together were of greatest influence in attracting flying A. aegypti, but a dark object at ambient conditions in the vicinity of a warm humid white target received almost equal attention from the flying mosquitoes. Incident illumination as low as 100 lux markedly reduced the attractiveness of an otherwise attractive surface. Movement had a consistently small but positive attraction, though the effects of this might be obscured by local air turbulence due to the motion.

It is necessary to demonstrate the host specificity of an exotic phytophagous insect before introducing it for the biological control of a weed. The widely-used "starvation test" made on economic plants is considered inadequate for this purpose and we propose that studies should be broadened to include the following: (1) study of the insect’s biology, including host–plant records, with particular attention to adaptations likely to restrict the host range, (2) review of the plants attacked by related insects, (3) determination of the laboratory host range of the insect, (4) investigation of the chemical or physical basis of host–plant recognition, (5) starvation tests on economic plants to confirm the limits of the previously established host range, (6) establishment of the insects’ potential effectiveness for weed control. A limited amount of feeding on economic plants in the laboratory is not reason for rejection, if other criteria show the insect has a high degree of specificity.

Steremnius carinatus (Boheman), once considered a scavenger, has become recognized as a pest of coniferous seedlings. The weevils breed in roots of fresh stumps and in buried slash on logged areas, and adults emerge by the end of the second summer after logging. Adults girdle young seedlings from near the root collar to 1 in. above ground level, but seldom attack the second year after planting. Adult weevils are long-lived, and can survive three or more winters, establishing broods each spring. They eat a wide variety of vegetation and fruits and other materials containing sugars and starches. Greenhouse trials demonstrated selective feeding on seedlings and field tests showed that the weevils breed in most coastal coniferous species in British Columbia. Rates of brood development ranged from 2 months at 80°F to 24 months in unheated outdoor conditions. Differences in rates of development, apparently related to temperature, were found between localities. Phloem may be suitable for oviposition 2 years after logging, but often is depleted by the feeding of other bark-mining beetles. Although some weevil damage is caused by emergents from stumps on rights-of-way, damage from larger populations emerging later from newly-cut sites may be reduced by planting immediately after cutting.

There seems to be no information about the feeding habits of the adult in Nepticulidae, a family of moths well known as leaf-miners in the larval stage which belong to the primitive section Monotrysia. The following observations seem therefore to be worth recording.

Two of the five Nearctic species of the subgenus Bombus Latr. occur in southern Alberta. Both are bush-inhabiting species. One, B. occidentalis Greene, is confined to the treed areas of southern Alberta whereas the other, B. terricola Kby., although found throughout the treed areas of the province, is much more prevalent in the central and northern regions. Both species emerge and establish nests early, and nest almost exclusively in hives reached by means of downward-sloping tunnels. Many queens of B. occidentalis camouflage or restrict tunnel entrances by dragging grass in and around them. B. occidentalis produced 8.6±0.5 eggs in the first broods, 4.2±1.1 eggs per cell in the second and third broods, and 6.6±0.9 eggs per cell in the fourth brood. This species is intermediate in rank among southern Alberta species of Bombus Latr. in its ability to produce wax. As are other early emerging species, it is heavily depredated by Psithyrus spp.