Chaitophorus canens new species described herein is a species with grey apterae that was found forming clones at the bases of willow trunks in Saskatchewan.

A sequential decision plan, based on the negative binomial distribution and providing for two infestation classes, has been derived for use in management of the alfalfa blotch leafminer, Agromyza frontella (Rond.), in southern Ontario. It utilizes counts of the eggs in leaflets of alfalfa, and in economic situations will provide growers with sufficient lead time to consider alternative action strategies. An appraisal of the plan by field scouts showed that it rated the infestation status of the leafminer correctly in 48 of 51 cases. Sampling time averaged 25 min per scout per field.

Eupelmus reduvii n. sp.—Female.—Average length of body 2.4 mm. Average wing expanse 4.6 mm. Head slightly wider than thorax, which is of equal width with abdomen. Antennæ sub-clavate, as long as thorax. Collar rather long, much narrowed in front and concave above. Anterior half of mesothotacic scutum convex ; a broad, longitudinal depression posteriorly, the anterior corners of which are extended on in the parapsidal furrows. Scutellum small, much narrowed in front.

Results are presented for a 4-year (1986–1989) cytological survey of the Simulium venustum/verecundum complex on the Avalon Peninsula, Newfoundland, Canada. Based on 4578 larval identifications from 72 sites, six species in the S. venustum/verecundum complex were found: S. truncatum Lundström (= S. venustum EFG/C), S. venustum CC2, S. venustum CC3, S. venustum AC(gB), S. verecundum Stone and Jamnback (= S. verecundum AA), and S. rostratum Lundström (= S. verecundum ACD). The possibility that S. venustum A/C and S. venustum Say (= S. venustum CC) exist on the Avalon Peninsula in low numbers cannot be excluded, although this is doubtful. Discoveries of EFG/C and CC2 reciprocal sex exceptions support the hypothesis that exceptional individuals are the product of crossover. Cytological results confirm the supposition that S. truncatum, S. venustum CC2, S. venustum CC3, S. venustum AC(gB), S. verecundum AA, and S. rostratum are all distinct species. Results are interpreted within the broader geographic context of the S. venustum/verecundum complex. Three new cytotypes are recognized: one, from Quebec, we place under AC(gB); the other two, from the eastern United States, fall under CC2.

The following new Pyraustinae from New Guinea are described and figured: Haritala szentivanyi, Aphytoceros hollandiae, Talanga nubilosa and T. iridomelaena.

Younger specimens dark purple above with pearly markings, lavender or lilac beneath; older ones maroon to almost black above, sides mottled with several shades of purple and brown. Head free, purple, with a broad, white transverse band across the front; oral region whitish; vertex with a distinct, white, sagittate mark from antennæ to prothorax; a black ocellus-like speck on the middle of the vertex; a few short bristles upon vertex and front; eyes dark, close behind antennæ upon a black patch narrowly surrounded by purple. Antennæ longer than the body, except in largest individuals, segments variable in relative length, but approximately in the ratio of 1:6:7:1.5 or 1:7:9:2; basal segments stout, as long as broad, brownish, with short, white bristles; second brownish at base, purple at middle, pearly apically, hairy distally; third purple, hairy, with obscure, whorled subsegments on apical half, broadening towards apex, penultimate subsegment swollen on one side; terminal segment purple, lanceolate in outline with five to seven distinct, whorled subsegments. Body ovate dorsally with a re-entering angle.

Cephus cinctus Norton (Hymenoptera: Cephidae), the wheat stem sawfly, is a well-established and important pest of wheat, Triticum aestivum Linnaeus (Poaceae), and its relatives in North America. Crop losses are caused directly by C. cinctus feeding inside wheat stems during larval development and indirectly when weakened plants lodge before being harvested. Understanding the factors that affect population dynamics of C. cinctus can help farmers to better manage it. Our study therefore explored how C. cinctus and natural enemy densities vary in space (southern Alberta, Canada) and over time. Five fields were sampled using an established protocol in fall 2019 and resampled in spring 2020; six additional fields were sampled in fall 2020 and resampled in spring 2021. Wheat stubs were dissected to record numbers of cut stems, C. cinctus larvae, and sources of larval mortality (i.e., parasitism, fungal infection). Densities of wheat stem sawfly and the impact of natural enemies varied between the sampled fields. No C. cinctus mortality was observed during the winter, indicating that C. cinctus population dynamics are not susceptible to mortality (abiotic or biotic) between years. Results of our study will be incorporated into new models to predict wheat stem sawfly phenology and risk to crop production.

Within Canada, Cerceris fumipennis Say (Hymenoptera: Crabronidae) is known to occur in Ontario and Québec but there is also one historic record from 1935 of two female specimens captured in Lytton, British Columbia. No other records have been recorded for the last 77 years. In 2012 and 2013, one male and four females were captured in a sweep net adjacent to a gravel parking lot in Merritt, British Columbia. Although there are differences in size and colouration between the British Columbia and eastern species, the variation between the populations does not warrant assigning a new name to this geographical race.

Four species of Exenterus were reared from the European pine sawfly, Neodiprion sertifer (Geoff.), in Ontario. An introduced species, E. abruptorius (Thunb.), last reported in Ontario in 1948, was recovered in very small numbers at one location. The native E. affinis Roh. (= E. walleyi Cush.) parasitized a small proportion of N. sertifer but was the main species attacking feeding larvae. The native E. nigrifrons (formerly called E. canadensis Prov.) and the introduced E. amictorius (Panz.) occurred at all sampled locations. Both species were more numerous in high than in low density populations of N. sertifer, but E. nigrifrons was more destructive, and E. amictorius less destructive, at high than at low density.

About 60% of adults of E. amictorius and 6% of those of E. nigrifrons eclosed in the same summer that attack occurred. Most were unlikely to have reproduced, owing to the scarcity of hosts. In both species females were more frequent in female than in male hosts.

Samples of N. sertifer cocoons in July were superior to larval samples in June and cocoon samples in August and the following May for measuring the rate of parasitism and the relative abundance of Exenterus spp. However, because of mortality of Exenterus before and after sampling, data based on the rearing of cocoons seriously underestimated the impact of the parasites.

The research program of the Division of Entomology is steadily evolving as surely as are the insects themselves. The broad outlines of today's program have been shaped through the years by central administrative policies, by the nature and significance of the problems encountered, and by the pressure of public demand; the detail has been affected primarily by the availability of trained staff and research facilities, by the quality of local leadership, and by pertinent developments in sister sciences. All of these are continuing influences, which, together with important recent developments and some weighty unpredictables, will determine the nature and scope of tomorrow's program. But certain trends in research seem clear. The subject is discussed under three main headings, with a final summarizing statement.

During the past four years Mr. Douglas C. Ferguson has collected dragonflies in Nova Scotia thereby greatly increasing our knowledge of the geographical distribution of these insects within the province. He very generously presented to the writer his entire collections comprising 327 specimens of 51 species, four of these being new records for the Maritime Provinces and two others being new for Nova Scotia. In the annotated list of species below these new records are indicated as follows: New records for the Maritime Provinces are indicated by a double asterisk (**). Records which are new for Nova Scotia only, are indicated by a single asterisk (*). A better representation of the widely distributed northern genus Somatochlora whould have been expected in a collection of this size made from the territory covered, in view of the fact that at least eight species are known to occur in thls territory. The reasons for their escaping capture is doubtless due, in part, to the restricted habitat occupied by many of the species, and in part to the difficulty of collecting specimens.

Adult female Tarsonemus ascitus Delfinado mites are recorded for the first time as phoretic on the grain-inhabiting lathridiid beetles Cartodere constricta (Gyllenhal) and Enicmus fictus Fall, and the rhizophagid beetle Monotoma picipes Herbst. The mites preferred to attach to the lateral and undersides of the prothorax of the beetles. The spatial distribution of T. ascitus on C. constricta in suction traps was determined as a guide to the numbers of beetles that would have to be collected to obtain reliable estimates of numbers of mites found per beetle. The mean numbers of mites per beetle was always smaller than the variance, and the spatial distribution of the mites followed a negative binomial distribution. The numbers of beetles required to be collected to provide a predetermined measure of the precision of the numbers of mites per beetle were calculated.

Among the acari there are many species that damage food products (Sinha 1964; Solomon 1936; Cunnington 1965). However, very little information is available on the effect of fumigation on these organisms. Amaro (1963) developed a technique for the fumigation of the eggs of Acarus siro L. that exploits some of the behaviour patterns and preferences of that species. Since this method cannot be applied to Tyrophagus putrescentiae (Schrank), a pest of stored products, an attempt was made to seek other methods by which eggs of this species of a reasonably uniform age could be obtained for fumigation.

Diapause development in Culex tarsalis Coquillett has been characterized by reduced blood-feeding to complete termination of ovariole development at or before stage IIa (Bennington et al. 1958; Schaefer and Washino 1970; Schaefer et al. 1971; Bellamy and Corbet 1973; Mitchell 1979). The role that diapausing Culex species have in overwintering arboviruses has been examined (Eldridge 1966, 1968; Eldridge et al. 1972; Reeves 1974; Eldridge and Bailey 1979; Mitchell 1979). Gonotrophic dissociation and its implications for survival of the vector and virus has been reviewed by Washino (1977). Eldridge (1966) indicated gonotrophic dissociation was possible in Culex pipiens L. incubated at low temperature and short daylength and later reported failure of ovarioles of prehibernating C. pipiens to mature following a blood meal (Eldridge and Bailey 1979). Eldridge et al. (1972) reported that Culex restuans Theobald exhibited gonotrophic dissociation in response to conditioning by short daylength and low temperature. Mitchell (1981) has reported blood-feeding and gonotrophic dissociation in a significant portion of diapausing Culex tarsalis from Colorado, when females were kept at 15°C and at short daylength conditions.

Tropidophryne melvillei Compere is apparently indigenous to the region of Kenya Colony, Africa, where it was found to parasitize Pseudococcus sp. (Compere, 1939). In 1948 this parasite was introduced into California from Kenya Colony by the Division of Biological Control of the University of California Agricultural Experiment Station (Smith and Flanders, 1949).

Ide (1935) has studied the various instars in the development of the nymph of Ephemera simulans Walker, but does not state the length of the life cycle. Neave (1932) decided that in Lake Winnipeg species of Hexagenia, a genus very closely related to Ephemera, took two years to complete the life history cycle. The length of the life cycle and the rate of development of the species of Ephemera have been discussed but never satisfactorily settled. The present paper attempts to answer these questions with respect to Ephemera simulans in Lake Wawasee.

Garry oak, Quercus garryana Douglas ex Hooker (Fagaceae), is part of a unique ecosystem in British Columbia, Canada, which is rich in rare and endangered plant species. Garry oak recruitment is critical to the existence of this ecosystem, therefore, the effect of Curculio occidentis (Casey) (filbert weevil; Coleoptera: Curculionidae) and Cydia latiferreana (Walsingham) (filbertworm; Lepidoptera: Tortricidae) on acorn germination is of great interest. Together these two insects infested 80.7%, 75.1%, and 51.3% of acorns collected in 1996, 1997 (low crop years), and 1998 (high crop year), respectively. Filbertworm infestation did not vary with crown level. Filbert weevil infestation did not vary with crown level during poor crop years, but significantly more filbert weevil-infested acorns were found in the lower than the middle and upper portions of the trees during the high crop year. Severely damaged acorns did not germinate, and acorns with light to moderate feeding damage had lower germination success than undamaged acorns, but growth of germinated seedlings in the light to moderate damage category was unaffected. This study showed, for the first time, that these two insect species infested a large proportion of Garry oak acorns on the tree in British Columbia, and that light to moderate damage of the acorn has relatively low impact on seedling growth.

Male: Length of body (dried) 5 mm., of the forewings 1.8 mm., of the hindwings 1.5 mm. Color of body black, the abdomen with a mid-dorsal brown line; legs dark brown.

This is one of the most common insects that flies throughout the summer months. It is also widely distributed; adults have been taken in widely separated parts of Europe, in Algeria, Caffaria, Bengal, Pondicherry, Brazil, and in the eastern and western parts of the United States. Packard writes of the species thus:-“Such cosmopolitan forms give rise to the suspicion that they are relics of a past geologic age, which is borne out by the fact that quite a gap separates it from its nearest allies.”