A troglobite species, Quaestus (Quaestus) acuminatus sp.nov., from the Cantabrian Mountains (Province of Asturias, Spain) is described and illustrated. The taxonomic position is discussed and data on its isolation and geographical distribution are given.

Various methods for recording the activity of insects have been reported (e.g. Park, 1935, 1937; Gunn, 1940; Hammond, 1953). In this type of investigation, three characteristics are desired in the method: a) the apparatus should be sufficiently sensitive for recording small movements in small insects; b) the portion of the apparatus in immediate contact with the insect should permit easy subjection of the organism to various environmental conditions; c) the apparatus should permit rapid and easy accumulation of data from a number of insects. Two methods have been developed in the present laboratory in attempts to meet as far as possible these desirable qualifications.

Hille Ris Lambers (1960) erected the genus Toxopterella for his new species, canadensis, collected in Ontario and New Brunswick from Crataegus. At that time he had seen only the alate form of the species from Sorbus described herein, not the fundatrix, which is almost indistinguishable from the fundatrix of Toxopterella canadensis H.R.L. Because of the similarities in the fundatrices and because of the unique characters that they have in common in this morph, we place the aphid from Sorbus in the genus Toxopterella H.R.L., 1960. But the alatae of the two species are distinctly different and we therefore place this species from Sorbus in a new subgenus Sorbobium.

Recent rearings of the geometrid Melanolophia imitata (Wlk.) by officers of the Vernon and Victoria, B.C., laboratories of the Forest Biology Division, Canada Department of Agriculture, have yielded a series of a new species of Casinaria for which the following description is offered.

Casinaria melanolophiae, new species

Female. Length 7 mm. Head thin, temple rather weakly receding for a considerable distance behind eye, and beyond rather strongly rounded to occiput; antenna with 29-31 segments, the shortest flagellar segments at least a little longer than broad; cheek short, about 0.30 breadth of base of mandible; ocelli large; greatest diameter of lateral ocellus twice as great as ocellocular space and three-fourths as great as post-ocellar line; head and thorax dullish, with granular sculpture; mesoscutum and scutellum densely, shallowly punctate, with punctures somewhat obscured by granular sculpture; sides of thorax finely granular and with only a few minute punctures; propodeum and abdomen as in C. semiothisae Wly.

The species previously recognized as Euxoa ridingsiana (Grt.) is shown to be composed of a sympatric pair of sibling species, Euxoa ridingsiana (Grt.) and Euxoa maimes (Sm.), which in the laboratory will produce viable F1 hybrids but no F2. Results of F1 sib and backcrosses show that the F1 males are fertile and the F1 females are infertile. In mating-bias tests conducted in laboratory cages, 74% of matings were conspecific and 26% interspecific. Differences in the diel periodicities of mating, which are about 2 h out of phase, may account for the mating bias. The duration of development of E. ridingsiana in the laboratory and its seasonal flight period in the field are about 2 weeks in advance of that of E. maimes. However, there is considerable overlap of the flight periods and, with the tendency of females of both species to mate several times, it is unlikely that the difference in seasonal emergence is enough to effect reproductive isolation. It is evident that, under natural conditions, reproductive isolation can be maintained entirely by species-specific sex pheromones. This mechanism of reproductive isolation is, however, apparently ineffective when moths are confined in cages in the laboratory.

Biogeographic considerations suggest that the differences in life-cycle timing and mating periodicities might have been adaptations to adjust development and reproduction to prevailing ancestral environments. If the initial differentiation of the 2 species occurred in isolation and included at least an incipient shift in the pheromonal mate-recognition system, it is possible that upon reestablishment of contact between ancestral populations the differences in life-cycle timing and mating periodicities acting in concert could have effected substantial, albeit incomplete, reproductive isolation. Subsequent selection to reinforce assortative mating to preserve coadapted gene complexes could then have resulted in differentiation of discrete pheromonal systems and attainment of species status.

Topical application of thiotepa on the adult male spruce budworm, Choristoneura fumiferana Clemens, at a concentration of 10 μg/insect resulted in 100% sterility. Unlike metepa, thiotepa did not have any apparent adverse effects on the competency of the sperms. Large numbers of male moths can be sterilized by allowing them to walk for 30 min on filter paper treated with a 2.5% solution of thiotepa in a 3:1 mixture of acetone and diffusion pump oil.

Egg: Ovate in shape, bluish green in colour, the surface divided by reticulations into small hexagonal areas. Laid singly on the needles of host tree.

First Instar: Head width 0.23 mm. Body 2.0 mm. in length and 0.23 mm. in width Brownish green body with light brown head.

Second Instar: Head width 0.5 mm. Body 4.6 mm. in length and 0.5 mm. in width. Body lined alternately with green and light green stripes. Spiracular line greenish white. Head brownish green.

For many years chemists and entomologists have been seeking the hypothetical ideal insecticide, namely, a material which is toxic to insects at an economical dosage, which is not injurious to the host plant or animal sprayed or dusted with it, and which does not leave on foodstuffs a residue that is poisonous to man or domestic animals. Certain organic compounds approach closer to this ideal than any products of mineral origin, and the successful use of these against same of our most injurious insects has greatly stimulated the testing of countless organic products for insecticidal value.

In July, 1959 I reared a polyembryonic encyrtid from a species of Lithocolletis attacking Alnus crispa (Ait.) Pursh in the lake region around Ohio, Nova Scotia. It represents a species and genus new to science.

Gibberella, new genus

Type species: Gibberella scutellata Miller, new species.

In the months of June and July the Red Pine (Pinus resinosa) and the white Pine (Pinus strobus) show by the exuding pitch that they are suffering from the attacks of an insect. The wounds occur on the main stem below, the insertion of the branch. On cutting into the bark the injury is found to be caused by a small larva, which, when full grown, measures 16 to 18 millimetres. The head is shining chestnut brown with black mandibles. The body is livid or blackish green, naked, with series of black dots, each dot giving rise to a single, rather stout, bristle.

The results of a three year study of the imported parasites of Diprion polytomum show that an eulophid parasite, Microplectron fuscipennis Zett., gives promise of becoming an important control factor of the spruce sawfly in Canada. M. fuscipennis is widely distributed in Europe, and its habits there have been fully discussed by Morris and Cameron (1935) and by Ullyett (1936).

Small numbers (147–388) of Olesicampe benefactor Hinz, a European ichneumonid parasite of the larch sawfly, Pristiphora erichsonii (Htg.), were released in Maine, Nova Scotia, and New Brunswick in 1967. The parasite became established and has survived through two winters at five release points, and three winters on three release sites; on two sites the continued survival of the parasites is unconfirmed because of the collapse of the host population. O. benefactor is known to disperse slowly and even if it is successful in controlling the sawfly in the release areas, control over large areas may require releases at many locations.The subject of the range of host densities at which parasite releases should be made to ensure the greatest parasite production per parasite released, and hence the greatest chance of successful establishment, is discussed.

The female and male of Asca acornis n. sp. are described and illustrated. This species occurs in arboreal habitats in the southern United States. The absence of the most salient diagnostic character of the genus Asca on adults of this species is discussed.

The existence of a diurnal cycle in the rate of production of acoustic signals by aquatic heteropterans has been observed by several workers (Leston 1955; Mitis 1936; Schaller 1951; Theiss 1983). These accounts all mention an increase in acoustic activity in early evening. Jansson (1968, 1973) determined that the single strongest component releasing acoustic behavior was light level in the genera Cenocorixa and Callicorixa and that different species of Cenocorixa had different maxima. The study reported here began as an examination of diel periodicity of song incidence in the corixid bug Palmacorixa buenoi but results were substantially different in kind from most other studies of this nature in the literature.

This study of the taxonomic units comprising the genus Odontaeus Dej. has occupied, for the past three years, by far the greater part of such time as I can devote to entomology, and yet it is with a feeling of dissatisfaction that the following conclusions are offered to coleopterists.

Two new species of the genus Lygus Hahn are described: potentillae from Canada, Alaska, and Colorado; and mexicanus from Mexico and Texas. Lygus abroniae Van Duzee is considered to be a typical member of the genus Lygus. The seasonal colour variations of the three species are noted, their relationships to other species in the genus are discussed, and their host plants are given.