Numerical analyses have been carried out on some lepidopteran genera to find the effect of minimizing the number of characters used; the validity of drawing conclusions about the internal structure of a group which formed only a small portion of the analysis as a whole; the effect on numerical classifications when some characters are unknown for some taxa; and the diagnostic value of characters. The add-a-point program has been used to identify and to indicate the phenetic affinities of additional taxa.

A new species, Micropeplus minor, is described from Oregon. The species is placed in the Staphylinoides group and an existing key is modified to include the species.

Four new species of aphids are described from Manitoba: Dactynotus brevitarsus from Solidago sp., Myzus valuliae from wild strawberry, Fragaria vesca L., Amphorophora stolonis from dewberry, Rubus pubescens Raf., and Nasonovia (Hyperomyzus) sandilandica from Crepis tectorum L.

The horn fly in Alberta has been reported as being parasitized by five species of Chalcidoidea (Depner 1968, Can. Ent. 100: 1057–1060). These identifications are corrected to Muscidifurax raptor G. & S., M. zaraptor K. & L., Eupteromalus viridescens (Walsh), Spalangia drosophilae Ashm., S. subpunctata Foerst., and S. e. erythromera Foerst. The last two were not known in North America; neither they nor the Muscidifurax spp. had been noted as parasitizing horn fly. The Spalangia spp. can be credited with parasitizing up to 40% of horn fly pupae in traps and the Muscidifurax spp. up to 30%. E. viridescens seems to be an adventitious parasite of horn fly.

In field studies gypsy moth males were attracted to synthetic cis-7,8-epoxy-2-methyloctadecane (disparlure), the female sex pheromone, and virgin females from 0900 to 2000 (Eastern Standard Time). The greatest numbers of males were lured to the synthetic attractant or the calling female from 1100 to 1500. These periods of male response are longer than reported in previous (1896 and 1932) New England investigations and suggest the possible recent evolution of a new diel rhythm of male sex pheromone response.

Attraction of the spruce beetle, Dendroctonus rufipennis (Kirby), to beetle-infested logs was reduced 99% by addition of 3-methyl-2-cyclohexen-1-one (MCH), the natural antiaggregative pheromone of the Douglas-fir beetle, D. pseudotsugae Hopkins. The synthetic attractant frontalin and α-pinene attracted few spruce beetles and its nominal attraction was nearly nullified by addition of MCH. Male spruce beetles responded to the natural and synthetic attractants in greater numbers than females. When MCH was added to these treatments, females predominated among the few beetles caught. The clerid Thanasimus undatulus Say was strongly attracted to treatments containing frontalin, whether or not MCH was added, but MCH alone was not attractive to this predator. Among 13 other species of scolytids caught, the most abundant were Scierus annectens Leconte and Hylastes nigrinus (Mann.). Two relatively rare species, Scierus pubescens Sw. and Xylechinus montanus Blkm., were attracted in unusual numbers to natural spruce beetle attractant. Intensive study is recommended of the possible use of MCH to prevent increase of spruce beetle populations.

Calling by female Lambdina fiscellaria lugubrosa (Hulst) occurred when terminal abdominal segments 8–10 were protracted, exposing an enlarged region in the intersegmental membrane between segments 8 and 9. Histological examination of this region disclosed paired glands situated ventrolaterally in the eighth segment. The glands were presumed to be pheromone glands, and differ from those described for other Lepidoptera, in their paired structure and ventrolateral position. More males were attracted to traps containing virgin females than to empty control traps, but only during the first half of the moth flight. Board and yellow carton sticky traps were superior to 3M and white carton traps. Behavioral observations suggested that the sex pheromone may serve as an excitant as well as, or instead of, an attractant, stimulating the male to searching activity.

Captive colonies of Vespula arenaria (Fabricius) and Vespula maculata (Linnaeus) were placed in the field during the summer and fall of 1972. The adults were free to forage, and the colonies developed normally. Nest temperatures were recorded at mid-afternoon, 6 days per week. Once each week, colonies were confined, brought into the laboratory, and placed in a cold room at 5 °C for 4 h. At the end of this period, the nest temperatures were recorded and the colonies returned to the field. Under field conditions, V. arenaria colonies maintained an average daytime nest temperature of 31 °C, and V. maculata colonies maintained an average daytime nest temperature of 29 °C. As they developed, colonies of both species were increasingly capable of resisting cooling at an ambient temperature of 5 °C. This ability to thermoregulate under extreme conditions peaked in early August for V. arenaria and in late August for V. maculata. In both species, the decline in the ability to thermoregulate was associated with the production of reproductives. It appears that the major function of thermoregulation in these two species is to provide a favourable temperature for the development of the young rather than to provide the colony with protection against low ambient temperatures.

A population index for the estimation of the neosistens stage of pine leaf chermid on white pine is described. This is based on the observation that increasing numbers of the chermid produce increased stunting of length of pine needles. A regression relating chermid population density to needle length produced a correlation coefficient of −0.88, suggesting that measurements of needle length alone adequately estimate chermid populations under most conditions. The numbers and distribution of needles that must be measured to estimate length with reasonable precision are calculated. The total sampling plan for the four cyclic generations of the chermid is reviewed.

With the current advances in insect population modelling, the need for more accurate simulation of temperature-dependent growth rates has become vital. The day-degree concept, with its linear temperature–rate relationship, has not been adequate for simulation of field populations under highly variable temperature conditions. Similarly, several of the non-linear relationships proposed in the past (Janisch’s catenary, parabola) have also been inadequate. All of these relationships produce large errors at temperature extremes.

This paper presents a comparison of various functions which have been used for developmental time estimation and an algorithm for a sigmoid function which can be used in simulations having either a calendar or a physiological time base. Validation of the algorithm is presented for three insect species.

A sex pheromone trap was studied as a quantitative sampling device in a biological monitoring scheme for codling moth populations in Michigan apple orchards. Factors influencing trap efficiency and the relationship of trap catch to adult moth density and the overall seasonal dynamics of L. pomonella are considered.

By correlating seasonal male moth catches to absolute infestation levels at harvest it was possible to indicate the density response of male moth catches in the pheromone trap (Sectar 1). Catch response was non-linear and the trap ceased to be indicative of higher infestation levels when accumulative catch exceeded about 100 moths/trap. Also, accumulative trap catches from the first few weeks of the season (before damage appeared) correlated well with eventual infestation levels indicating possible use of the pheromone trap as a predictive tool. Of the many factors influencing trap catch size the number of moth productive trees serviced by a trap (trap/tree ratio) was shown to be of critical importance.

Synopeas osgoodi n. sp., associated with balsam gall midge, Mariaville, Me., U.S.A., and Platygaster kimballi n. sp., associated with thistle, Houlton and Belfast, Me., U.S.A., are described herein.

Where the insecticide Zectran was used to protect foliage from feeding of the spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae), the per cent parasitism of dipteran parasitoids (Tachinidae) showed a statistically significant lower value. In treated areas, the per cent parasitism of the hymenopteran Ephialtes ontario (Cresson) (Ichneumonidae) was lower; Meteorus trachynotus Viereck was about the same; Apanteles fumiferanae Viereck, Glypta fumiferanae (Viereck) (Braconidae), and Trichogramma minutum Riley (Trichogrammatidae) were greater. None of these differences was statistically significant. Results were consistent for the 2 years of study with the exception of E. ontario which showed a significant lower percentage parasitism in areas treated 1 year. Absolute population numbers of parasitoids were lower than is suggested by comparisons of apparent parasitism levels. The lowest absolute numbers were found in tachinids and E. ontario. Parasitic hymenopterans and dipterans were among the adult insects killed by the aerial application of Zectran but none of the species collected was a major spruce budworm parasitoid.

Perilampus salicetum Steffan (Chalcidoidea) is removed to the monotypic Steffanolampus (gen. nov.). The type series was dubiously reported as being taken in either Austria or the Far East but the species has been subsequently found only from Quebec to Maryland and Michigan, as well as in Washington State. It is associated with several anobiid beetles.

A second specimen of Holcopsis fenestrata Enderlein, previously known only from the type and with the locality in question, is reported from Mexico. Some diagnostic and comparative characters of the species are noted.