The following notes consider very briefly a very large field. They apply primarily to zoological systematics. They reflect my respect for the thoughtful field naturalist and, probably, some other prejudices. They reflect my inrerest in the species rather than in the higher categories, and are of course influenced by the limitations of my experience.

Agrilus anxius Gory has been reported as breeding in numerous species of birches and poplars. Because species of Agrilus are often poorly characterized morphologically, and usually restrict their feeding to one or to a few closely allied species of plants, it has been suspected that two species were confused. Barter, working in New Brunswick, noted that male specimens reared from, or artracted to, birches and poplars were separable allvays by characters of their genitalia. He found also the differences in biology which described below. Study of material in the Canadian National Collection and the U.S. National Museum shows that the genitalic characters hold in specimens associated with food-plants in other localities. Smith (1949, Nature 164: 237), working with material reared in New Brunswick, found that males and females from birches have 22 chromosomes, and those from poplars only 20. Thus it has been demonstrated that two species, one feeding on birches, the other on poplars, have been confused as Agrilus anxius.

In a paper published during the war Reeks pointed out that the sawfly which has caused much damage in the forests of Canada for about twenty years is identical with Lophyrus hercyniae, described by Hartig in 1837. In the same work he proved that Hartig was correct in describing hercyniae as a species distinct from Lophyrus polytomus Htg. Enslin's view that the two species should be united under the name polytomus is quite wrong. Reeks has shown that important biological and anatomical differences exist between them. Benson erected the genus Gilpinia for the species polytomus and for allied species. Reeks was unable to examine the types of the two species, kept in the Hartig collection in Germany, and for that reason he sent to me some specimens of the “European spruce sawfly” from Canada, with the request that I compare them with the types in the Hartig collection. The results of my examination are as follows.

It has been brought to my attention by G. E. Bucher, that in my note on the generic assignment of the spruce budworm Choristoneura fumiferana Clem. (Can. Ent. LXXIX: 21, 1947) I cited the genotype as Tortrix rusticana Treit. This citation is a laps. cal. for Tortrix diversana Hbn., the correct genotype as contained in my original manuscript.

On the warm afternoon of August 29, 1948, as I was walking through a wheat stubble-field on my farm located six miles southwest of McMinnville, Oregon, I became aware that I was in the midst of a dragonfly migration. I could see them all about me for a radius of perhaps seventy-five feet which was about the limit of my vision for an insect of this size. When first seen there was a considerable number passing toward the west with from thirty-five to fifty of the insects visible at any given moment but after about five minutes they began to thin out until only a few were visible. I then walked south for two hundred feet at which place another heavy concentration was encountered. After a short interval these thinned to a few stragglers. Thinking that the migration was about over I retraced my steps only to meet with another wave. It soon became apparent that the migration was taking place orer a wide front and that the insects tended to fly in groups over the valley floor.

Pleurotropis utahensis Crawford was first reported as a parasite of the wheat stem sawfly, Cephus cinctus Nort., by Crawford (2) prior to 1913. It has been recorded by Crawford (2) from Kimball and Salt Lake City, Utah; by Ainslie (1) from North Dakota; and by Gahan (5) from Missoula, Montana. It is one of several parasites of the wheat stem sawfly in the Prairie Provinces of Canada, where it has been recorded (7) (8) as far west as Sylvan Lake, Alberta. Criddle (3) (4), and in his original notes, records it from as far east as Boissevain, Manitoba. During the present study this parasite has been collected from sufficient locations that one might assume that it occurs throughout the area where wheat stem sawfly is found (6) in Alberta, Saskatchewan, and Manitoba.

On August 28, 1949, over beach drift and seaweed at Matane on the Gaspé Peninsula, Quebec, the writer collected a series of flies presumed to be Coelopa frigida (F.). Later examination revealed the capture of two males of Orygma luctuosa Meigen, a peculiar coelopid fly with small eyes, extremely broad cheeks, and broad, flat facial carina. Inasmuch as this European species had apparently been recorded only once before from North America, it seemed desirabie to place the find on record.

One female and a damaged male of this rather extraordinary physogastric beetle were brought into the laboratory early in November, 1946. A few days later four further males and three females were collected from the same situation, a roadside bank of hard calcareous clay facing SSW, at Mill Creek, Edmonton. In view of the many references to this insect rn entomological literature, but the scanty information given on it, some laboratory observations were considered worth while.

A species of tent caterpillar which occurs in the prairie region of Canada, from southern Manitoba west to the foot-hills of Alberta, and which often occurs as a pest on rose, cherry, and gooseberry has been referred to as Malacosoma fragilis (Stretch) (properly fragile). In 1881, Stretch described fragile from Virginia City, Nevada, and an examination of Stretch's type in the American Museum of Natural History showed that this species possesses a grey ground colour and in this respect is quite unlike the fawn-coloured species from the Canadian prairie.

The commercial production of apples has led growers to greater reliance on chemical control measures for pests than have most fields of agricultural production. Since the turn of the century orchardists have plunged deeper and deeper into artificial measures to produce fruit free from blemishes without greatly alleviating the over-all pest problem and, in some cases, actually producing conditions conducive to still greater problems.

One of the few Canadian entomologists to study thrips was R. C. Treherne who was one of the group of workers to investigate the pear thrips when it first became an economic pest in North America. In the course of his work he collected and studied thysanoptera. His collection, supplemented by exchanges with other workers, formed the basis for the material now in the Canadian National Collection at Ottawa. The writer is indebted to curators of this collection and particularly T. N. Freeman, for the generous loan of valuable specimens for study, particularly the types of Treherne. The Moulton collection is now deposited at the San Francisco Academy of Science, Golden Gate Park, San Francisco, California. We also wish to thank Dr. E. S. Ross, curator, for the opportunity of studying the types of Taeniothrips tahoei Moulton, Tae. pingreei Moulton, Tae. aureus Moulton, and Frankliniella californica Moulton.

Early in March of 1948 I was asked by a member of the staff of the Royal Ontario Museum of Zoology, Toronto 5, Canada to identify the fleas in their collection. Never having worked fleas east of the Rocky Mountains or to any extent in British Columbia I suggested that the collection be sent to a Canadian specialist or to Dr. Karl Jordan of the British Museum. I was not in the least displeased, however, when on the first of April a packet containing the collection arrived at my home in Tigard, Oregon.

The genera Nearctopsylla Rothschild 1915, Corypsylla Fox 1908, and Corypsylloides Hubbard 1940, all apparently strictly Nearctic, comprise a natural group which is intimately associated with certain mammals of the Order Insectivora. A subfamily, Nearctopsyllinae, of the Hystrichopsyllidae, has recently been proposed (Holland, 1949: 102) to accommodate these three genera, which are well separated from other fleas on the basis of a number of well marked morphological characteristics.

During the summer of 1949 an outbreak of flea beetles on both sweet and silage corn occurred at Armstrong, British Columbia. The first damage to the corn was noticed by the growers in early July, and by mid-August was so severe in some instances that the crop had to be cut for ensilage before the cobs were mature. The adult beetles confined their feeding to the leaves and cob husks, causing decided browning and drying out of these areas.

In a preliminary paper on the role of small mammals in the natural control of the European spruce sawfly, Gilpinia hercyniae (Htg.), the writer (7) recorded that shrews have a remarkable ability to select sound cocoons in preference to those which are dead or emptied by parasites. This ability was said to be much less apparent, however, in the rodents. However, various experimental aspects of the project on natural control were not completed. This was due mainly to the severe decimation of the sawfly resulting from the combined attacks of small mammals, disease, and parasites. Since the above statements have elicited some interest, it secms worthwhile to present the data on which they were based. Other aspects of the project, particularly those concerned with the populations of small mammals and their relation to forest site, and with the role of larval Elateridae, will be reported later.

In biological research it is often desirable to rear and handle animals free from microorganisms. This is particularly true in nutritional studies in which it is generally recognized that certain orgnisms in the digestive tract can supply nutritional factors which might otherwise be lacking in the diet. The possibility of this intervention makes it necessary to devise techniques for rearing and handling insects aseptically, in so far is the fauna and flora of their intestinal tract and of their environment are concerned. Consequently, a technique used throughout the present series of studies was developed making use of specially designed equipment by means of which nymphs of the cockroach, Blattella germanica (L.), were hatched and maintained under aseptic conditions, fed aseptic food, and kept aseptic throughout a series of measurements to evaluate their weight increment. The equipment and methods used constitute the basis of the present paper.

The spiders considered here were collected by Dr. Francis Harper during the period from May 31 to December 4, 1947, in the vicinity of Nueltin Lake, Keewatin, Canada while on a trip made under the auspices of the Arctic Institute with support from the Office of Naval Research.

A general account of the area and field notes have been given by Harper (1948, pp. 153-184) and Henry W. Fowler has presented a taxonomic report on the fishes (1948, pp. 141-152).

Eleven species of spiders belonging to five families are represented by mature specimens; and juveniles, not determinable to species, add another family.

The taxonomic status of Ephemerella excrucians Walsh was recently discussed by Burks (1947), who also stated that destructive ecological changes have drastically altered the type locality of the species. Special interest attaches, therefore, to two male specimens of Ephemerella which I reared from nymphs taken in the Au Sable River, Crawford County, Michigan, and which Dr. Burks has determined as E. excrucians.

RecentIy I received from Dr. Clifford O. Berg a series of specimens of a diapriid reared from puparia of Sepedon fuscipennis Loew, a sciomyzid fly, the biology of which he has been investigating at Sodon Lake, Oakland County, Michigan. The species falls in Phaenopria as that genus is currently recognized, and it is apparently ancdescribed. At the suggestion of Dr. Berg, I am naming it in honor of Mr. Gustavus D. Pope, the owner of Sodon Lake which he has made available for research to the Cranbrook Institute of Science for a period of three years. Mr. Pope, who is a trustee of the Cranbrook Institute, has a serious interest in the research sponsored by that organization and has done a great deal to make it possible. It is, therefore, with particular pleasure that I dedicate this new species to him.