Biological control attempts against the weed Hypericum perforatum L. in the interior of British Columbia are summarized. Three of the insects introduced, Zeuxidiplosis giardi Kieff., Agrilus hyperici (Cr.), and Chrysolina varians (Schall.), did not survive, and reasons for their failure are discussed. Two beetles, C. hyperici (Forst.) and C. quadrigemina (Suff.), are established and their population build-up in several areas is followed over a period of 15 years. The beetles reach their optimum effectiveness in different moisture zones but neither species is effective at the arid end of the H. perforatum range. A moth, Anaitis plagiata L., was released in this zone in 1967.

The possibility of imperfect coincidence between the appropriate stages of Neodiprion sertifer (Geoff.) and two of its important parasites was demonstrated. One of the parasites, the indigenous ichneumonid Exenterus canadensis Prov., which attacks late-stage larvae, has good spatial coincidence; but some members of each generation suffer from imperfect temporal coincidence, or asynchrony, caused by the interaction of temperature influence on parasite development rate and temperature variability between development sites in the litter. The second parasite, Pleolophus basizonus (Grav.), is an introduced, multivoltine ichneumonid cocoon parasite. It may be imperfectly synchronized in its first generation each year and may show imperfect spatial coincidence in all generations through its inability to attack host cocoons beneath approximately 1 in. or more of litter.The intricate relations between parasite and host density, time, attack, and coincidence were investigated using the basic functional response submodel developed by Holling, a submodel that describes changes in oviposition behaviour with time, and a submodel that predicts the number of hosts attacked, given the number of eggs laid and data on the distribution of eggs among hosts. In the two species studied, the effect of asynchrony in one generation cannot be considered without considering the influence of superparasitism. At low host densities, superparasitism largely buffers the effects of decreased synchrony. This buffering effect decreases as host density increases until when each parasite is attacking all the hosts it can, it is almost eliminated. Imperfect spatial coincidence in one generation merely lowers the usable host density. Thus its effect can be seen in the functional response of the parasite to host density. When host–parasite interactions over 25 to 35 host generations were simulated, using initial conditions resembling those ensuing when small numbers of both host and parasite invade a previously unattacked stand, populations became stable after passing through one or more oscillations. Decreasing temporal or spatial coincidence increased host and parasite densities at the peaks of oscillations and increased the ultimate steady density of host and parasite, until coincidence was reduced to nearly half. At this level, the host escaped the regulating ability of both species of parasites.

The following new taxa are described: Pseudopolygrammodes n. gen., type-species Polygrammodes priscalis Caradja, western China; Proteurrhypara n. gen., type-species Opsibotys ocellalis Warren (= Pyrausta discimaculalis Hampson), Japan; Proteurrhypara ocellalis apoialis n. subsp., Hokkaido, Japan; P. chekiangensis n. sp., W. Tien-mu Shan, China; P. occidentalis n. sp., Li-Kiang, N. Yuennan, China; Opsibotys perfuscalis n. sp., Honshu, Japan; and O. flavidecoralis n. sp., Li-Kiang, China. Pyrausta fuscobrunnealis South is transferred to Opsibotys.

Based on bomb calorimeter determinations, the calorific values of four sizes of larvae of Galleria mellonella (L.) fed to nymphs and adults of the predator Podisus maculiventris (Say) increased with increase in larval size. Correspondingly, these values for P. maculiventris nymphs in fourth and fifth instars and adults, male and female, increased when the predator fed on larger larvae. Increases in energy consumption resulted in increases in energy loss due to respiration and egestion for nymphs and adults of the predator. For unfed males and females, calorific values decreased with age, i.e., as initial body energy reserves were used up.No significant differences in mean calorific values were observed for fertile and infertile eggs laid by females reared at each of the four diet levels. This suggests that the amount of energy utilized by females in the production of eggs is fairly constant, irrespective of the amount of energy consumed at each diet level.Energy budgets for nymphs of P. maculiventris showed that gross efficiency of growth for second- and third-instar nymphs was inversely proportional to energy consumed; however, no such relationship was observed for fourth and fifth instars. For males, energy budgets showed that at all diet levels little growth took place during adult fife, with gross efficiency at diet levels 1 to 4 ranging from 0.88 to 2.20%. For females, some growth occurred at all levels of diet during the first 35 days of adult life, mainly as a result of the production of eggs. Gross efficiency during this period ranged from 5.5 to 13.6%. Efficiency of reproduction at diet levels 1 to 4 ranged from 37.26 to 45.35% during the first 35 days of adult life and from 39.46 to 51.16% for the next 20 days.

The face fly, Musca autumnalis De Geer, is continuously present in the field at Guelph, Ont., from April to late October, with peak populations occurring near 1 August. The flies enter buildings only to hibernate, the females doing so in an unfertilized, nulliparous condition. The flies feed only during the daylight hours and primarily on cattle and horses. Infestations on these hosts arc subject to wide daily and hourly variation dependent on temperature, light, precipitation, wind, and behavior of the host.Mating normally occurs as a result of males waiting at particular stations in the pasture to apprehend females flying past. Experiments and observations on a laboratory colony of face flies has disclosed other facets of their sexual behavior.Provided with a suitable proteinaceous diet the face fly can produce an average of 26 eggs per ovarial cycle and a probable maximum of near 230 eggs in a lifetime. Oviposition and (or) successful development will apparently occur only in bovine feces having a certain consistency. Face flies are among the first of the coprophagous insects to reach a dropping; arriving normally within 5 to 10 minutes of its deposition. The dropping remains suitable for oviposition for up to about 3 hours, depending on the rate of drying of its surface.Under normal summer temperature conditions eggs hatched within about 24 hours. The young larvae were initially restricted to the surface layers of the dropping by their respiratory requirements but by the end of the normal 5 to 7 day development period the larvae occupied the entire dropping. Mature third stage larvae pupated in the soil surrounding the dropping.Two hymenopterous pupal parasites Aphaereta pallipes (Say) and Xylaphora sp. accounted for approximately 10% mortality. Face fly adults were preyed upon by the staphylinid beetle Ontholestes cingulatus Gravelle, and the common dung fly, Scatophaga stercoraria (L.).

A generalized competition model for predators or parasites was developed from data obtained from a specific parasite–host system. It was structured in three parts. The first simulates the effects of exploitation, where the number of attacks and their distribution among prey or hosts determine how many prey or hosts survive. Since the negative binomial distribution described these distributions consistently, the exploitation submodel was developed from it. The second portion of the competition model concerned interference between searching predators and parasites. Although interference is a universal phenomenon, we were able to show that its effects become important only at predator densities much higher than those that occur in nature. Thus the interference component can be essentially ignored. The third and final component concerned the outcome of competition between parasite progeny within their host. It was developed from Fujii’s competition model which allows for the simulation of both scramble and contest types of competition.These three submodels of competition were combined and coupled with a previously published model of the effects of prey density on attack. In this way the full consequences of different prey and predator densities could be simulated using a model whose constituent parts had been carefully tested for descriptive adequacy. The simulations showed the way individual predator attack, per cent predation, and progeny production were affected by different degrees of contagion in the distribution of attacks, by scramble vs. contest competition, and by the degree to which parasites could avoid hosts already attacked.

Dendroctonus brevicomis Lec. responded in flight to combinations of insect- and host-produced volatiles. Emergent female beetles crushed at −70 °C, as well as synthetic exo-7-ethyl-5-methyl-6, 8-dioxabicyclo [3.2.1] octane (“brevicomin”) attracted both sexes of the western pine beetle when offered with oleoresin freshly tapped from the host, Pinus ponderosa Laws. Offered separately, these materials were inactive. Crushed emergent Dendroctonus ponderosae Hopk. males per se, however, attracted flying D. brevicomis in appreciable numbers. Dominance of either host odor or insect pheromone appeared to govern the sex ratio of the responding insects.

The New World species of the staphylinid subfamily Oxyporinae are revised. Only one genus, Oxyporus Fab., with two subgenera, is included in the subfamily. The genus Pseudoxyporus, described by Nakane and Sawada (1956), has been reduced to subgeneric rank. Sixteen species are included in the revision. Two new species, O. bierigi from Costa Rica and Panama, and O. balli from Mexico are described; two names are placed in synonymy [O. fasciatus Melsh. (= O. vittatus Grav.) and O. fenyesi Bernhauer (= O. mexicanus Fauvel)]; and two names are reduced to subspecific level [O. bicolor Fauvel (= O. vittatus bicolor) and O. austrinus Horn (= O. femoralis austrinus)]. All of the New World species and subspecies have been redescribed and illustrated, and a key has been included for the separation of all the taxa.

Dioryctria tumicolella, from pine blister rust, Peridermium spp., swellings on Pinus ponderosa Lawson and Son in British Columbia, Washington, Montana, and Colorado; D. contortella, from Peridermium swellings on P. contorta Douglas in British Columbia, Alberta, and Washington; D. monticolella, from trunks of P. monticola Douglas in British Columbia; and D. banksiella, from trunks of P. banksiana Lambert in Alberta, Northwest Territories and eastward, are described as new species and distinguished from the western D. cambiicola (Dyar) and the eastern D. zimmermani (Grote).

Roepkea, as here understood, consists of 10 species whose primary or winter hosts are the Pruneae and the Pomeae and whose secondary or summer hosts are mainly the Leguminosae. R. marchali (Börner) is the only endemic Palaearctic species known. The Nearctic species are: bakeri (Cowen); crataegifoliae (Fitch); kachena (Hottes); multisetis new species; punctata new species; sclerosa new species; sensoriata (Gillette and Bragg); yohoensis (Bradley); zabapsis new species. A key and host index is provided.

The opisthosomal musculature of adult female Araneus diadematus Clerck was investigated by means of dissections. Forty-nine different muscles, each paired, were found in the opisthosoma proper. Of these muscles, 7 pairs move the opisthosoma about the pedicel, 13 pairs compress the opisthosoma, 19 pairs move the spinnerets and colulus with respect to the opisthosoma, 4 pairs dilate the anus, 3 pairs dilate the genital aperture, and 3 pairs open the book-lung spiracles.

A new genus Scalponotatus is described, with nine new species from North America: maturus from Arizona and California, and albicornis, albipes, capitatus, chillcotti, howdeni, insignis, mexicanus, and mimosus from Durango, Mexico. Strongylocoris albibasis Knight is placed in this genus (n. comb.). A key is provided and male genitalia of all the species are illustrated.

Amber of Cretaceous Age from Canada is an exceptionally fine source of well-preserved fossils of a wide variety of insects and related animals. Since these fossils can yield much information about the forms of, and conditions for, life in the Cretaceous Period some 75 million years ago, they represent a highly interesting and valuable scientific resource.The history, relative abundance, nature, biological origin, and significance of Canadian amber is reviewed and related to similar aspects of European or Baltic amber. Reported occurrences of amber in Canada (about 50) are assembled and some 350 arthropod inclusions discovered in the amber collections made thus far are tabulated, with respect to their origins, classification, and present location. The article contains one map, two tables, and 16 figures.

The upper limit for continuous development of Pleolophus basizonus lies between 25° and 30 °C since all stages develop at the former temperature and larval mortality is complete at the latter temperature. The lower limit lies between 5.5° and 10 °C, since an eonymphal diapause occurs at 5.5 °C. Between these extremes, diapause incidence varies inversely with temperature. The photoperiod experience of the parent has no effect on diapause in the progeny when the latter are reared at 15° and 18 °C, but there is an inverse relation between parental photoperiod experience and progeny diapause incidence at 10 °C. Although larvae and pupae also survive 3 months at 2 °C, most individuals probably overwinter in eonymphal diapause and their diapause requirements are fulfilled in 3 weeks at 2 °C. The incidence and rate of post-diapause development is directly related to temperature.

The life histories of Pseudohylesinus tsugae Swaine and P. grandis Swaine were investigated in young coastal stands of western hemlock. Both P. tsugae and P. grandis had one generation a year with two broods and four larval instars. P. grandis usually overwintered as a teneral adult and P. tsugae as a fourth instar larva. Within thinned stands P. tsugae preferred fresh stumps for breeding material, whereas P. grandis preferred fresh slash. The adult females of both species fed in the inner-bark region of standing, live host trees before initiating egg galleries in slash or stumps.

An artificial diet for rearing the codling moth is described. It is a modification of a casein–wheat germ diet that was initially developed for the cabbage looper. Agar was replaced by a mixture of wood sawdust, wheat flour, and wood pulp. Growth of microorganisms was controlled by sorbic acid and aureomycin, and by lowering the pH of the diet to 3.5 with citric acid. Production cost for dietary ingredients was about $1/1000 moths. The moths were slightly smaller than those reared on apple. When confined in cages, the sterilized diet-reared moths were somewhat less competitive than the apple-reared insects. However, sterilized diet-reared male moths released in an apple orchard dispersed more rapidly than sterilized apple-reared males.

Unsprayed apple trees measurably increased the numbers of the Oriental fruit moth, Grapholitha molesta (Busck), in adjacent peach trees in only 1 of 4 years, though the apples were rather heavily infested. The moth became evenly dispersed throughout a previously uninfected peach orchard within three generations. Caged orchard trees were unsatisfactory for studying behaviour because the environment within the cages differed from that in the orchard. Experimental studies indicated that fecundity of the females was variable between years and generations and a varying proportion laid no eggs. Intraspecific competition between newly hatched larvae occurred at low egg densities; egg mortality was small but mortality of newly hatched larvae was large.

Of the methods designed to detect and measure the intensity of direct and delayed density-dependent types of mortality acting on populations, that of Morris has gained considerable acceptance. While this method of analysis has predictive value and provides a means of estimating direct density-dependence, it seems inappropriate to the detection and measurement of a delayed density-dependent mortality such as that normally associated with entomophagous parasites. The biological significance of the slopes of the linear regressions calculated in the Morris method is discussed, and population models based on the theory of Nicholson and Bailey are presented in support of the argument.