Choristoneura fumiferana (Clemens) and C. pinus pinus Freeman are redescribed, and the following five forms are described as new: C. biennis, British Columbia; C. occidentalis, Washington; C. orae, British Columbia; C. viridis, California, Oregon; C. pinus maritima, Pennsylvania, Massachusetts, New Jersey, Kentucky.

Field collections of late instar larvae of Choristoneura populations were obtained from a wide range of localities. These populations were found to fall into nine taxonomic entities, either species or subspecies. A tenth group is of uncertain affiliation. Five of these entities have tree species of the subfamily Abieteae as their hosts, whereas the other four (probably five) characteristically feed on species of the subfamily Pinoideae. Furthermore, each of the budworm species, or subspecies, is associated with a characteristic forest region.

Pigmentation of heads and prothoracic shields of last-instar larvae, colour of pupae, and frequencies of haemolymph colour morphs in fresh pupae are used to support the taxonomic differentiation of the following members of the genus Choristoneura: fumiferana, biennis, orae, occidentalis, viridis, subretiniana, pinus pinus, p. maritima, and lambertiana. These characters are statistical in nature and not competent to relate a single individual unequivocally to a taxonomic group; nevertheless, a key is developed to assist identification of populations on the basis of the characters described. Interspecific relationships within the genus are considered.

Tests of sexual isolation indicate that, in the absence of temporal and spatial isolation, the strict mating behavior of the females and the high sexual aggressiveness of the males of Choristoneura fumiferana (Clem.) would obstruct any inward flow of genes from either C. occidentalis Free, or C. biennis Free. Under these same conditions, however, the two latter species may receive genes from C. fumiferana, since, in tests, their females mated indiscriminately and their males were less aggressive than those of C. fumiferana.

The newly named C. biennis has a two-year cycle characterized by a second period of diapause at the end of the third instar. Second diapause occurs to varying degrees in C. fumiferana, C. occidentalis, C. orae, C. pinus pinus, and many of their hybrids, but has not been recorded in C. viridis. Although the incidence of second diapause can be influenced by the length of photoperiod to which larvae are exposed after completion of the second-instar diapause, second diapause occurring naturally is not primarily under environmental control. Laboratory studies have demonstrated differences in the incidence of second diapause manifested by these species and by some of their hybrids that point to the existence of genetic differences between them. This evidence supports the newly gained taxonomic status of these insects.

Although additional papers of this series are in preparation, it is considered appropriate to publish the completed ones at this time and to present this interim, tabulated, summary of the preceding five papers to assist the reader in the recognition of the forms with which we have already dealt. Other forms occur on conifers in the mountainous regions of western Canada and the United States that are not well known taxonomically. When studies on them are completed, it is the intention to prepare a final summary of all work that has been done on this subject.

Data are given on the biology of several species of Trichoptera in the Metolius River, Oregon, based on drift and benthos samples. Twenty-seven species were collected. Species of Limnephilidae, Brachycentridae, Hydroptilidae, and Lepidostomatidae were important drift components. The Metolius River is extremely productive, with a mean density of larval Trichoptera of 7400 per square meter in benthos samples and a maximum of 5000 per 24 hours in drift-trap samples. Different species varied in their tendency to drift, in the age class distribution in the drift, and in diel periodicity. Drift-trap collecting is shown to be a useful method of studying aspects of behavior such as the dispersal of larvae and the emergence of pupae.

Diapause induction in Hyphantria cunea is under the joint control of photo-period, temperature, humidity, food quality, and possibly other variables, but insufficient data are available to permit a precise evaluation of their actions and interactions. Short daylength and low temperature induce diapause and the critical thresholds for New Brunswick – Nova Scotia populations are in the vicinity of 14.3 hours and 72°F, respectively. Low humidity increases the incidence of diapause, as does also the change in the nutritional quality of foliage late in the season. Both field data and the extrapolation of laboratory data to field conditions indicate that the occurrence of a partial second generation is unlikely in this area, even in warm seasons.

This paper reports on studies of biology and life history of the Zimmerman pine moth, Dioryctria zimmermani (Grote), in southern Michigan.

Adults emerged during the last 3 weeks of August and eggs hatched through mid-September. Eggs were laid almost entirely on the main stem and, upon hatching, the larvae entered recesses in the bark and spun hibernacula, ostensibly without feeding.

Studies on the vertical distribution of larvae and pupae showed a fairly uniform distribution over the main stem in spring and early summer. In late summer, a larger percentage was found in middle whorls.

Based on head capsule measurements, it is tentatively proposed that there are six larval stadia. Occurrence of parasitism in the last larval stadia is discussed, and a new egg parasite is reported.

The presence of D. abietivorella Grote in the study areas is noted, and discussed briefly.

Tinocallis Matsumura is a small group of aphids that is mainly associated with the Ulmaceae. Eight species are known, as follows: Tinocallis ulmiparvifoliae Matsumura, T. platani (Kaltenbach), T. saltans (Nevsky), T. zelkovae Dzhibladze, T. zelkowae (Takahashi), T. ulmifolii (Monell), T. caryaefoliae (Davis), and T. kahawaluokalani (Kirkaldy). All are redescribed and an illustrated key is offered.

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

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.