The following are descriptions of a new species of the subfamily Typhlocybinae from northern Canada, and one new species of the subfamily Deltocephalinae from Eastern Canada and a second from the Prairie Provinces. The type material is in the Canadian National Collection, Ottawa.

In Western Canada, Aedes flavescens (Müller) is found mainly on the prairie, where it is one of the commonest of the blood-sucking pests of livestock and man. It has also been taken as far north as Churchill, Man., and Alaska (Rempel, 1950). Information on its flight range is useful in planning control programs. Field and laboratory studies on the flight range of this species, with radio-active phosphorous for tagging, were conducted at Saskatoon and Indi, Sask., in 1952. The project area is almost flat in the north and west and rolling in the south and east; the Blackstrap Valley separates the two topographical areas.

The application of lethal agents of any kind in entomological research is usually aimed at the determination of mortality as related to such factors as dosage, temperature, and time. Mortality is the yard-stick and survivors merely the fraction that did not die. After an arbitrarily selected interval the experimental material is categorized as dead or alive, with sometimes an intermediate group such as “subnormal” inserted. This third class is often essential, for its members do not properly qualify as dead or alive, terms that imply totality. It is also a nuisance, for several reasons: (1) it blends gradually into the other two categories so that classification itself is subject to errors of judgment; (2) its numerical uncertainty affects the other categories not only at the time of initial classification but also later by the death or total recovery of some of its members; (3) as long as any treatment-effect persists, the situation remains quantitatively incomplete.

In studies of sawflies, the family Pamphiliidae has been much neglected especially from the morphological stand point. Yuasa (1922) made a study of the larvae, but the genus Cephalcia was dealt with rather briefly. Ross (1937) and Benson (1945) made comparative morphological studies of the adults and showed the phylogenetic position of the family. More recently, Middlekauff (1953) published a description of Cephalcia marginata, a pine web-spinning sawfly which was the subject of the present study.

Cabbage and related crops are attacked every year throughout Ontario by caterpillars of three species, namely, the imported cabbageworm, Pieris rapae (L.), the diamondback moth, Plutella maculipennis (Curt.), and the cabbage looper, Trichoplusia ni (Hbn.). The imported cabbageworm is generally regarded as the most abundant of the three species and is reported as doing damage of considerable economic importance each year. The cabbage looper does not occur in large numbers until late in the season, but in most years it is believed to be second only in importance to the imported cabbageworm. The diamondback moth is generally considered to be much less important than the other two species (Caesar, 19i8). As previously reported (Matthewman et al., 1952), these beliefs were not borne our by observations of field populations at Ottawa in 1950. Whereas populations of the cabbage looper were strikingly low, those of the diamondback moth were much higher than the literature indicated. This paper is a summary of four seasons' experiments, 1951-1954, undertaken to assess the abundance and relative importance of the three species in eastern Ontario.

Wilted stems of Eupatorium odoratum L., (Compositae) in Trinidad were found to contain an egg or lama of a Curculionid. Each egg was deposited in a slit between two rows of punctures encircling the stem. This girdling made by the ovipositing female was obviously the cause of the wilting. Larvae hatching from the eggs fed for a few days ih the wilted portion of the stem and then tunnelled into the sound tissue below the punctures completing development a month later, and pupating in the stem near the base of the plant. The adults, which emerged ten days later, were identified as Rhodobaenus sp. nr. cariniventris by Mr. R. E. Warner of the U.S. National Museum.

The usual criterion of insectidal effectiveness is the mortality suffered by test insects exposed to insecticides. Often, investigators disregard the sex ratio when selecting test insects for exposure. Demonstrated differences in susceptibility between male and female insects require evaluation of the sex ratio in studies on insecticidal effectiveness.

At a locality nine miles southwest of Fresnillo, Zacatecas, Mexico, a number of females of Dasymutilla formicalia Rohwer and males of D. pallida Mickel were observed around our campsite during the second week of August, 1954. However, all of the males and most of the females were active only in the early morning and late afternoon. On August 10th, in a dirt roadway about three-quarters of a mile from camp an unusually large concentration of these mutillids was discovered at about 6 p.m. Since but a single species of Dasymutilla appeared to be involved the following observations on the activities of the males and females were recorded.

In the come of the study of parasites of mealybugs for introduction into West Africa for the control of mealybug vectors of cocoa virus a number of undescribed Encyrtids have been discovered in Trinidad, B.W.I. Descriptions of these and new Encyrtids reared from other hosts will be published in a series of papers.

The present paper records three species of Pseudaphycus from Trinidad, two of which are described as new. I am indebted to Mr. H. Compere who stated (in litt.) that the species herein described were probably new and pointed out the characters that separated them from related species. Dr. B. D. Burks kindly compared specimens of these species with types of related species deposited in the United States National Museum and suggested slight alterations in the manuscript which have been duly made.

In Vol. 87, p. 256, captions for Figs. 13 and 15 should be reversed, p. 261, line 5, (Fig. 30) should be (Fig. 16), line 6 (Figs. 11, 12) should be (Figs. 19, 20), line 7, (Fig. 3) should be (Fig. 26).