This paper includes descriptions of a new species of Iziphya Nevsky and one of Euschizaphis Hille Ris Lambers. The former genus is well represented in North America, but Euschizaphis, which is best known for its association with the Juncaginaceae, has not been previously recorded from the western hemisphere.

Iziphya punctatella, new species

Apterous Viviparous Female.–Colour when alive: Ground colour of head and body yellow with black spots around the bases of most of the setae (Fig. 4). Antennae dark except for the basal half of segment III which is yellow; apex of rostrum dark; legs black except apical two-thirds of tibiae which are colourless. Colour when macerated: Essentially as when alive, but yellow areas colourless or nearly so.

There are five known North American species in the genus Hylobius; H. pales (Hbst.), H. congener Dalla Torre, H. pinicola (Couper), H. radicis Buch., and H. warreni Wood. In recent years four of these species have increased considerably in economic importance in central and eastern Canada and the eastern United States; H. pales and H. radicis attacking pines and H. pinicola and H. warreni attacking spruces and pines. H. congener occurs only in small numbers and little is known about its ecology. It is important, therefore, to be able to separate these species readily in the field.

The family Opomyzidae is composed of small (2.0 mm.-4.4 mm.), slender, usually brown or reddish flies; the wings have at least an apical spot and are usually more heavily marked. Several species of the genus Geomyza have the wings reduced and are nearly flightless. The few species whose larvae are known feed in grass stems. Some are of minor economic importance in Europe but none have been so reported in North America.

In subarctic Canada conventional methods of correlation and regression analyses were inadequate in relating periodicities in mosquito flight to fluctuating physical environments (Haufe, 1958). The periodicity for individual species shifted in relation to sidereal time. In addition to a random component in the variation, a gradual shift was associated with the advance of the season for consecutive cycles of activity. For the most abundant species it appeared as older individuals constituted an increasing proportion of the natural populations. The relative variations in absolute values of light and hygrothermal conditions identified with 24-hour flight periodicities were inconsistent with seasonal variations in 24-hour meteorological cycles. If light was a primary factor in the activation of natural populations in the 24-hour cycles, observed variations in correlations would suggest variable adaptation of mosquitoes to previous light conditions and to other physical and biological factors.

This paper describes a new species of the genus Dasiops Rondani, which is known to be a primary pest of apricot fruits in California (Moffitt and Yaruss, 1961). In common with other Lonchaeidae, the adult of this species is small (about three mm. long) and rather stout; with a shining, metallic blue-black body; the female possesses a long, piercer-wpe ovipositor (Figs. 5-7) similar to that of otitids and trypetids. Other characters that serve to distinguish the family include: black halteres, hairy frons which is narrower in the male than in the female (Figs. 1, 2), a single, reclinate upper frontal bristle, diverging postvertical bristles, a row of bristles near posterior nargin of the mesopleuron, one or more sternopleural bristles and (usually) bare ptero- and hypopleuron. The genus Dasiops can be distinguished from other genera of Lonchaeidae by the presence of tiny, forwardly directed poststigmatal bristles which arise in the depression above the mesothoracic spiracle just cephalad of the anterodorsal corner of the mesopleuron.

In a recent discussion of the subject of insect resistance to insecticides, Brown (1958) has claimed that true resistance is characterized by a five-fold to ten-fold decrease in susceptibility. It is a genetic phenomenon arising as a result of selection. There is no evidence that insecticides are mutagenic, nor can resistance be induced by exposing insects to sublethal doses. A decrease in susceptibility that cannot be regarded as resistance is regarded as a condition of tolerance. In addition, the term “vigour tolerance”, intioduced by Hoskins and Gordon (see Brown, 1958) defines instances of enhanced tolerance due to extra vigour: true specific resistance is marked by a change of slope in the dosage-mortality regression line, while “vigour tolerance” is suggested if the regression line shifts but does not change in slope.

During 1958 a general infestation of Pineus coloradensis (Gillette) was observed on red or Norway pine, Pinus resinosa Ait. This insect is widely distributed throughout western United States where it attacks a number of pines. The Annand collection has a slide with specimens of P. coloradensis (Gillette) taken from red pine on the Universitv of California campus dated February 10, 1925. However, there are few reports of any Pineus species attacking red pine in its natural range from the region of the Great Lakes to the Atlantic coast. Shenefelt and Benjamin (1955) have reported the white pine bark aphid or a closely related form on red pines in Wisconsin. Bean and Godwin (1955) also mentioned the presence of an unidentified species of Pineus on red pine.

In recent ecological studies on the European pine shoot moth, (Rhyacionia buoliana (Schiff.)), where a major objective was to evaluate the influence of different hosts on oviposition preference, larval mortality, insect size, rate of development, and sex ratio, the inadequacy of conventional growth measurements was much too apparent. There was a need to document relatively small differences in larval size and rate of growth on several hosts or from one stand to another. Measurements which showed growth but not weight or volume losses have limited value where the insect under study has a long non-feeding period. Such measurements as body length, and especially head capsule width, obviously belonged in this category. On the other hand, it was felt that dry weight measurements would show both gain and loss. Further, a volume estimate (or body index) would be even more useful, if one could be devised which bore a linear relationship to dry weight. Such an index, while it might involve more than one measurement, nevertheless could be made without destroying the larvae.

Testing arthropods for their ability to transmit plant viruses depends on a satisfactory means of confining test specimens on plant hosts while excluding all other arthropods. This can be difficult with small, active insects such as the Thysanoptera. Screen or cloth capable of confining them must be of such fine mesh that adequate ventilation is prevented and condensation becomes a problem.

A study of the genus Diaphnidia Uhler showed that D. debilis Uhler, the type of the genus, was markedly different and not congeneric with the five other species hitherto included. A new genus, Diaphnocoris, is described for four of these: pellucida Uhl. (type), capitata Van Duzee, crockeri Van Duzee, and provancheri Burque; the fifth species, heidemanni Knight, is considered to belong to Brachynotocoris Reuter. Following are descriptions of the three genera of this group as now considered.

The author (1959) reported on four species of Hymenoptera that had not been previously recorded as parasites of the armyworm, Pseudaletia unipuncta (Haw.). During further studies at Ottawa four more new records were obtained: Three species were primary parasites, namely, Netelia sayi (Cush.) (Ichneumonidae), Nepiera marginata (Prov.) (Ichneumonidae), and Microplitis alaskensis Ashm. (Braconidae); and one species, Catolaccus cyanoideus Burks (Pteromalidae), was a secondary parasite. N. marginata and M. alaskensis were also reared from larvae collected at Kapuskasing, Ontario.

The nesting biology of Hoplitis producta has been reported by several authors, as the species is a common and widely distributed bee in North America east of the Rocky Mountains. Additional records, which have been obtained in connection with trap-nest research on bees and wasps in Wisconsin, are provided to supplement the previous reports.

The nests were found in the pith at the butt ends of sumac stick trap-nests. A nest could be recognized readily because the 3 mm. plug that closed the burrow had a more solid texture and a darker color than the surrounding pith at the end of the stick. Rau (1928) found nests in tunnels of elder, sumac or rose stems but could not ascertain whether the bee excavated its own burrows or utilized burrows left by other twig-dwellers. Fischer (1955) stated that the female almost invariably excavated its own burrow. In Wisconsin, freshly cut sumac sticks were placed in the field in the spring; therefore, each of the following records represents a nest in a burrow excavated by the foundress bee.

The genus Anoplonyx Marlatt belongs to the more generalized of the Nematinae and is clearly defined taxonomically by Ross (1937). This genus is comprised of very few known species, four in North America and four in Europe; all are associated with trees of the genus Larix. The species are similar in appearance and difficult to distinguish, especially in the adult stage.

Considerable confusion existed concerning the identification of the members of this genus in North America up until Wong (1955) published a key to separate the late feeding stages of Anoplonyx larvae found in Canada. The two species dealt with herein are apparently native to Eastern Canada and have generally been identified as one species, “Marlatt's Larch Sawfly”, A. laricis (Marlatt). Here they are identified as A. luteipes (Cresson) (= laricis Marlatt), and A. canadensis Harrington, as listed bv Ross (1951).

In eastern Canada larvae of the spruce budworm, Choristoneura fumiferana (Clem.), complete their development in one year, undergoing only one period of winter diapause in the second instar, whereas in certain parts of British Columbia, at high altitudes, two years are normally required for development, the larvae spending a second period of winter diapause in the fourth instar (3, 9). Among laboratory-reared eastern budworm there are a few individuals that enter a similar second diapause (7). The low incidence and somewhat irregular occurrence of this second diapause in eastern budworm, even in laboratory rearings, have hitherto made detailed studies almost impossible, but unusual storage times and treatments used recently in rearing experiments had the unexpected effect of increasing the incidence of this tvpe of behaviour to a level where experimental analysis became possible. This paper describes these larvae and their behaviour; an account of the effects of various conditions upon the incidence of second diapause will be presented later.

It was suspected for many years that the electrical environment stimulates insect activity. Schùa (1952) found that alternating potentials caused guard bees to become hostile and foragers to increase their activity and food uptake. Levengood and Shinkle (1960) reported that the progeny yields of cultures of Drosophila melanogaster Meig. in an electric field were, on the average, higher than control groups and the effect of barometric pressure was considerably reduced. The present study was made to determine whether electrostatic fields of low intensity affected the oviposition rate of a hymenopterous parasite.

A few years ago, Urquhart and Beaudry (1953) published the first North American records of Metrioptera (Roeseliana) roeseli (Hagen.) which had been discovered near the Montreal airports in July, 1952 (Ville St. Laurent, 12. VII.-1952, 3 ♂) (Professor Beaudry (in litt., 1960) actually cites 4 ♂); Montreal, 16.VII.1952, 1 ♂; 19.VII.1952, 1 ♂). It was suggested that the species had been introduced by aircraft at some previous date. Subsequently Professor Beaudry (in litt., 1960) has taken the species in suitable grassy localities at several points on Montreal Island (Montreal, 7.VII.1953, 1 ♂; Ste Geneviève, 15.VII.1953; Mount Royal, 9.VII.1959, 1 ♂;) and the neighbouring islands of Ile Perrot (1.VII.1953, 7 ♂, 1 ♀; 3.VII.1953, 1 ♂, 3 ♀) and Ile Jesus (St. Martin, Lava1 Co., 7.VII.1953, 1 ♂). He has also encountered it subsequently all around Montreal; at Bois-des-Filion (just on the mainland north of Ile Jesus) it was “very common” during the summer of 1960.