Prey avoid predators in a wide variety of ways. Grasshoppers of the alpine habitat exhibit predator-avoidance posturing. Furthermore, they show sexual diethism (behavioural differences between sexes) in which the males of Aeropedellus clavatus (Thomas) and Melanoplus marshalli marshalli (Thomas) prance (hop without progression), tending to face the oncoming threat, more so than the females. The latter do not prance to the same extent and more frequently face away from the threat. On the plains, Melanoplus bivitattus (Say) and M. sanguinipes sanguinipes (Fabricius) tend to assume a sideways stance relative to the oncoming threat. Neither plains species exhibits sexual diethism in avoidance behaviour. Prancing occurs in the plains species but, in males, is less frequent than in alpine species. These different predator-avoidance behaviours are apparently related to the need for the grasshoppers to maintain surveillance of potential predators in habitats of different temperature regimes and density and height of cover.

The following new Pyraustinae are described: Goliathodes n. gen., type-species G. shafferi n. sp., New Guinea and Waigeu; Spoladea mimetica n. sp., New Guinea; Meekiaria n. gen., type-species M. lignea n. sp., New Guinea; Aiyura n. gen., type-species A. linoptera n. sp., New Guinea.

In British Columbia, native willows (Salix spp.) (Salicaceae) and, to a lesser extent, black cottonwood (Populus trichocarpa Torr. & Gray) (Salicaceae) are frequently attacked by the poplar and willow borer, Cryptorhynchus lapathi (L.) (Coleoptera: Curculionidae). Red alder (Alnus rubra Bong.) (Betulaceae), trembling aspen (Populus tremuloides Michx.), and bigleaf maple (Acer macrophyllum Pursh) (Aceraceae) are not attacked. We studied olfaction and feeding preferences in the laboratory and feeding, oviposition, and emergence in the field. Female C. lapathi preferred Scouler's willow (Salix scouleriana Barratt ex Hook.) over all other species by olfaction, but males did not discriminate between Scouler's willow and black cottonwood or trembling aspen. All species elicited at least some attraction in no-choice situations. Willow was generally preferred for feeding, but black cottonwood and red alder were also acceptable, unlike trembling aspen or bigleaf maple. In field caging experiments, adult weevils emerged from willow, black cottonwood, and red alder. We conclude that olfaction and feeding preferences are sufficiently powerful to mediate the frequent attack observed on native willows, the intermediate levels of attack on cottonwood, and the absence of attack on red alder. Successful development on red alder suggests that C. lapathi could expand its host range to include this species.

This wasp has been reported capturing as prey the western harvester or mound-building prairie ant, Pogonomyrmex occidentalis (Cresson), and carrying it on its sting or on the posterior end of the abdomen to its nest. During the month of September, 1932, the writer was again privileged to wasp and to make some further observations.

Melitœa Chalcedon, ab. fusimacula.— Variations of Chalcedon are very common, but the ones I now describe are so striking that they are certainly worthy of a varietal name, especially as they do not seem to be so very uncommon. In the first of these, to which I have given the name Fusimacula, there is a tendency to obliteration of the spots on discs of both wings, and to a fusion of the three outer rows of spots in a horizontal direction. The ground colour of the upper surface is of the same rich black as Chalcedon. There is a complete absence of the spots in the cells of both fore and hind wings in males, and there are but faint traces of them in the females. On the fore wings the fusion takes place as follows: The two outer rows unite to form a yellow band, which is joined at about its middle by a yellow demi-band from the costa, which is composed of the fusion of the two inner rows.

A molecular and biometric assessment and redescription of Myzodium mimulicola (Drews and Sampson) are provided. New North American host and distributional data are presented, including the first record from Alaska. Myzodium knowltoni (Smith and Robinson) is a junior subjective synonym of M. mimulicola, based on molecular-sequence and morphological evidence. A key to the known Myzodium species (apterae and alatae) is included.

A substantial amount of the mustard and a small amount of the canola seed produced in the prairie provinces in 1983 was downgraded due to excessive content of insect frass. Because the frass was similar in size to the seed, much of it was not removed by the usual cleaning processes. Most seriously affected was mustard seed which has a contamination limit of 1 frass pellet per 500 g for grade Nos. 1, 2 and 3 Canada and 0.005% by weight for No. 4 Canada (Can. Grain Comm. 1983). Initially the limit for canola was 0.02% by weight based on tolerances established for rodent (vertebrate) excreta. Because insect (non-vertebrate) excreta is less detrimental than rodent excreta, the limits for non-vertebrate excreta in canola marketed within Canada were increased to 0.1%, 0.2% and 0.3% for grades No. 1, 2 and 3 respectively (per. comm., L. Sequin, Deputy Director, Standards and Technology, Canadian Grain Commission). The previous limit of 0.02% remains in effect for canola entering the export market. Similar consideration was given to revising the limit for insect excreta in mustard seed but no change was made because the quality criteria are quite different; canola is extracted for its oil whereas mustard seed may undergo little processing before being consumed.

The preceding part under this title was published in 1946 (Can. Ent., 77: 186-191). I am here discussing a number of species from the western United States, chiefly from Oregon and California, where they were collected by my friends, Messrs. T. H. G. Aitken, Mont A. Cazier, Kenneth M. Fender and Lawrence W. Saylor, to whom I am greatly indebted for the privilege of retaining the types in my collection. A few additional species were taken by myself in Arizona and Wyoming.

♂ Head dark olive-brown, tinged with paler ochreous around the base of the antennae and behind the ocelli ; thorax deep black-brown, the pleural sutures marked with ochreous; abdomen dorsally light clay-color with deep brown semi-rectangular lateral patches, extending forward and downward from the posterior margin of each segment but not attaining the anterior margin except on segments one and two where they occupy nearly the entire segment; ventrally similar in color to dorsum with lateral longitudinal brown streaks or bands adjoining the suture; forceps and setae dull smoky.

Serious damage to the seeds of wild rice, Zizania aquatica L., is caused annually by the larvae of a noctuid species hitherto unidentified and with little of its life-history known. In the summer of 1957 larvae reared from eggs found in the heads of wild rice were determined as of the species concerned, and in March, 1958 an adult reared from the same lot was identified by Dr. D. F. Hardwick, Entomology Division, Ottawa as of Apamea apamiformis (Guenée).

Last instar larvae and the pupae of Gluphisia avimacula, Notodonta simplaria, Dasylophia thyatiroides and Hyparpax perophoroides are described, compared with those of related species, and in part figured. Various ecological aspects are discussed and host plant information is provided in each case, with comments on the number of generations, times of occurrence and, with respect to simplaria and thyatiroides, on the regional prevalence of melanism.

Sexual size dimorphism occurs in many species. Differences between males and females, in size or other characteristics, may result from sexual selection, fecundity selection, natural selection, non-adaptive processes, or a combination of these pressures (Darwin 1874; Selander 1966; Trivers 1976; Slatkin 1984; Shine 1989). In insects, females with large body size often produce more eggs than smaller females, and femalebiased sexual size dimorphism is commonly attributed to such fecundity selection (e.g., Preziosi and Fairbairn 1997; but see Leather 1988). Water boatmen are detrivorous or zoophagous aquatic insects often inhabiting small ponds of the Northern Hemisphere (Hungerford 1948; Nosil and Reimchen 2001). Female water boatmen are generally larger than males. In this note, I quantify the nature and magnitude of a previously undescribed sexual size dimorphism in a natural population of the water boatman Callicorixa vulnerata Uhler (Hemiptera: Corixidae). I tested for differences between males and females in mean trait size (body length, body weight, mid-leg tarsal length, mid-leg tarsal spine number), and also tested for sexual dimorphism in allometric relationships between tarsal traits and body length.

In the Canadian Entomologist, during the year 1898, I gave a series of papers on the classification of the horntails and sawflies, representing the superfamilies Siricoidea (Xylophaga) and Tenthredinoidea (Phyllophaga); while the past year, 1899, I gave a classification of the entomophilous wasps, or the superfamily Sphecoidea (incorrectly spelt Sphegoidea).

The simple fact which Mr. W. H. Edwards published in this journal last May has thrown great doubt over the relationship of all the American species of Cyaniris. From eggs laid in September, 1874, by C. Pseudargiolus, he reared in the following February C. violacea. From this fact he is led to conjecture that in W. Virginia, where his experiments were made, C. neglecta may prove to be a goneutic form of the same species, reducing the entire series in that district to one.

267. Euxoa nesilens, Smith(Jour. N.Y. Ent. Soc. XI., 192, Dec., 1903). —Described from Calgary and from Brandon, Man. The type is a Calgary specimen in Prof. Smith's collection, and a ♀ co-type is in my own. The description says: “In general appearance it resembles siles, but does not have the black basal streak, nor the blackish suffusion between the ordinary spots. On the other hand, it does have more complete, better marked median lines … Its distinctness is clear, and its association is with basalis, from which, however, it differs obviously in colour.”

In many organisms, habitat affects ecological and genetic diversity and, for certain species, it is expected that a large population should have higher genetic diversity than a smaller population. We analysed the genetics of males of the orchid bee, Eulaema nigrita (Hymenoptera: Apidae) and examined the links between local abundance and habitat with genetic diversity. We also investigated the impact of landscape features on genetic population structure, through microsatellite and mitochondrial DNA analysis, among populations found across 700 km of Brazilian Atlantic forest fragments. We found that genetic variation was not a function of local abundance, but it correlated significantly with habitat. There was significant but low genetic differentiation among populations. We found a single mitochondrial DNA haplotype in all sequenced specimens, which may be widespread throughout the Atlantic forest. Our results reinforce the idea that orchid bees can fly long distances. High-dispersal capacity, together with insufficient time in eventual isolation, can directly contribute to the high degree of similarity among populations for this species, despite their wide geographical distribution.