A list is given of a total of 82 species of animals, mainly insects and mites, taken from the bracket fungus Polyporus betulinus (Bull.) Fr., growing on dead birch in Gatineau Park, Quebec.

Diel patterns of emergence, flight, host-seeking and oviposition have been studied in two mosquitoes, Aedes (Ochlerotatus) impiger and A. (O.) nigripes, at Hazen Camp (71° 18′ W., 81° 49′ N.). Diel periodicities were detected in both species for all these activities except flight. Oviposition of A. nigripes shows a well-defined pattern, but otherwise periodicities are evident only as slight and somewhat irregular diel fluctuations. All diel patterns show a maximum near solar noon, and appear to result from a direct (exogenous) response to ambient temperature. The patterns of host-seeking flight, closely similar in both species, are compared with those recorded for Aedes (Ochlerotatus) at lower latitudes. Small morning and afternoon peaks at Hazen Camp are seen as vestiges of sunrise and sunset maxima that characterize this periodicity further south.

Seven indigenous and four introduced species of aphids occur on ferns (Polypodiaceae) in North America. A new species, Macrosiphum cystopteris, is described, and Macrosiphum sleesmani Pepper is designated as type of a new genus Papulaphis.

Feeding of the potato leaf hopper, Empoasca fabae (Harris), on broad bean caused injury manifested at the cellular level by cell hypertrophy. The action of insect saliva was studied under closely controlled conditions by using cultures of broad bean tissue. The initial feeding experiments are reported and a description is given of the nature of feeding sheaths in tissue culture.

Examination of tissue cultures of broad bean fed upon by the potato leaf-hopper suggested that the nature of the sheath was similar to that produced in organized bean tissue. The sheaths could be recognized by the same criteria–the presence of collar-like deposits on the surface of the tissues, the filiform nature or the sheath, the characteristic red staining of the sheath material and the occurrence of enlarged and empty cells adjacent to the sheath. However, feeding in tissue differed in having no specific direction, and in the presence of pools of secretion sometimes found at the base of the sheaths.

A new species, Teratocoris borealis, is described from Northwest Territories. T. viridis D. & S. is reported for the first time from the Nearctic Region. T. herbaticus Uhl. and T. lineatus Wagn. are synonymized with saundersi D. & S., T. caricis Kirk. (= longicornis Uhl.) is reinstated as a good species. Species are keyed and male genitalia are figured.

The species of Bothromus Townes and Townes are discussed from the standpoint of their taxonomy, distribution and hosts; and a revised key to species is presented. Bothromus bicolor n. sp. is described from Alberta, British Columbia, Quebec, South Dakota and Washington.

Known material of the subtribe Mekongianina is reviewed. The group comprises four little-known flightless, montane species from S.W. China and S.E. Tibet: Yunnanites coriacea and Mekongiana gregoryi, which are micropterous, and two apterous species, kingdoni and wardi, which are here transferred to a new genus, Mekongiella.

St. Helen's Island, the site of Trichoptera studies in 1964 and 1965, is described. The Trichoptera encountered are listed, and taxonomic notes given where appropriate. Catches from a light-trap operated nightly in each year provide information for the different species concerning: relative abundance, frequency and seasonal range of occurrence, pest status, and sex ratio. Of the 99 species recorded, eight were classified as pests (causing a nuisance at light), six having this status in both years; together these eight species made up 87.6% of the seasonal total in 1965. Between late May and late September 1965, when large numbers arrived at light (median nightly catch ca. 3 × 103), a nuisance occurred on about one third of nights. Excluding Psychomyia flavida, of which only females were taken at light, most species showed a slight preponderance of males, but sex ratios varied widely according to species, year and night of capture.

In the Niagara Peninsula, Ontario, leaf galls produced by fundatrices of the grape phylloxera, Phylloxera vitifoliae (Fitch), first appear soon after the beginning of shoot growth. The infestation builds up later as the result of almost continuous gall formation by at least four overlapping generations of gallicolae, until at the end of the growing season galls may be up to 2000 times more numerous than in the fundatrix generation. A portion of the first-instar crawlers hatched in leaf galls migrate, fall, or are blown from the foliage to the soil, beginning when second-generation gallicolae hatch, and reaching a maximum late in August, probably after the fourth-generation gallicolae begin to hatch.

Pithanus maerkeli (H.-S.) and Actitocoris signatus Reut. are Holarctic in distribution, and the latter is recorded for the first time from North America.

A list is given of 77 species of arthropods, taken in 1965 from the bracket fungus Fomes fomentarius (L. ex Fr.) Kickx growing on dead birch, in Gatineau Park, Quebec.

The immature stages of Epinotia nanana Treitschke are described. Keys are presented for the eggs, larvae, and pupae of the four lepidopterous needle miners known on spruce in Ontario.

Eretmocerus californicus is a solitary parasite of numerous whitefly species. It is able to develop in all nymphal stages of its host but prefers the second and third. Oviposition and development of the first-instar larva take place under the host, the following two instars develop endoparasitically. Superparasitism is common under artificial conditions, but the supernumeraries are always eliminated during their first or second instar. Adult longevity is highest at 60° and lowest at 100° F. Males are rare and superfluous in Riverside but abundant and essential in Indio. In Riverside, E. californicus is most abundant during the late summer and is almost absent from the field between January and June. In Indio, it is present the year around. Although it attacks the same host instars as Encarsia pergandiella Howard, no hyper- or multiple-parasitism takes place. E. californicus is an important controlling factor on whiteflies in the Coachella and Imperial valleys but not in Riverside and the coastal area.

The following organs were investigated histologically for evidence of neurosecretion during the adult life of Bombus fervidus queens: supra- and sub-oesophageal ganglia, frontal ganglion, ventral nerve cord, corpora cardiaca, and corpora allata. The anatomy and histology of these organs are described, along with the secretory products found in the median neurosccrerory cells. A type of neurosecretion that seems unique to Hymenoptera and that appears later in the life of the queen is discussed.

A study of halictine nests in a habitat near Toronto leads to the discovery of an undescribed species of the genus Dialictus that shares morphological resemblances with Dialictus rohweri (Ellis) and architectural similarities with Augochlorella striata (Provancher).

The capture of Itoplectis conquisitor (Say) is being reported as the first record of this ichneumonid as a parasite of the European corn borer Ostrinia nubilalis (Hübner) in Canada.