Lameere (1917), in a paper dealing with the evolution of mayflies recognizes the moult between subimago and imago as a mere delamination of the outer layer of cuticle resulting in a lighter more fragile imago. Needham (1935) agrees with this contention and states that the subimago “does not represent a growth period and is therefore not a true instar.” Further, “It is only a casting of the delaminated, hairy outer cuticle.” This is a recent view and at variance with the more conventional one that both the subimago and imago represent separate insttars.

During the past three years a great deal of attention has been paid to the use of derris and pyrethrum as basic, non-poisonous insecticidal material. This work was stimulated primarily by the tolerance placed upon arsenicals and other so-called poisonous insecticides. Considerable progress has been made and a number of formulae have been developed for the control of certain insect pests with the use of derris and pyrethrum that give safe, effective and economical kill. New applications are constantly being devised and it is the purpose of this paper to briefly review some of the newer developments in the field of derris and pyrethrum investigations.

It is often more convenient to call an insect hy its common name than by its scientific name. This doubtless is the case with Microcephalothrips abdominalis (Crawford). Watson (1923) first referred to this thrips as the “Compositae Thrips” and, in view of its decided preference for members of this plant family, it seems appropriate to adopt this common name.

In 1930, the spruce sawfly, Diprion polytomum (Hartig), was found severely defoliating spruce trees in the interior of the Gaspe Penninsula in Quebec. At that time it was estimated that some 2,500 square miles were affected. Since then the infestation has increased in intensity and extent, and in 1936 the sawfly was known to be present throughout most of the spruce forests of north eastern America from the eastern boundary of Ontario to Nova Scotia (I).

Calliopsis andreniformis is a panurgine bee that inhabits much, if not all, of the eastern area of the United States. It is a small inconspicuous species. The females are about 8 mm. in length, exclusive of antennae, quite robust, general color gray, abdomen fasciate, maculation luteous. The males are more slender, smaller, maculation yellow, face and legs entirely yellow.

Traces to section 77 in Muesebeck's key (Proc. U.S.N.M., LVIII, 493, 1920) but differs from all species falling under that section as follows: at once distinguished from etiellae and cassianus by having the ovipositor sheaths as long as abdomen; differs from victoriae in having the wings clear hyaline and from monticola which it appears to resemble more closely, in being somewhat larger, with scutellum impunctate, propodeum without a trace of a median carina and the radius of fore-wing uniting with transverse cubitus in a rounded obtuse angle.

Heterocloeon curiosum McD. (1923)

The reduced median caudal filament of the nymph and the presence of a metathoracic wing in the adult would place this species in the Acentrella subdivision of the genus Baetis. This nymph is one of the commonest in the streams investigated but is confined to the lower, warmer reaches.

September 23, 1935, the writer exaimined the wharf of the Atlantic Sugar Refineries Limited at Saint John, N.B., which was under reconstruction owing to “decay” of the timbers. The officials of the company had discovered that these timbers had been riddled by borers which proved to be the larvae of an oedemerid beetle, Nacerda melanura L. As the references to this insect in the literature are scant and there is uncertainty as to its economic importance, the following notes are presented.

The fact that the swallowing muscles have not yet been described for any member of the order Odonata was first brought to the writer's attention in the course of studies on the mechanism of moulting and hatching of I. verticalis. A previous writer on that subject had described an Odonate nymph as swallowing water without the use of any stomodeal dilator muscles, which he had assumed were absent.

T. melanorhinus Big. I have a specimen from north-eastern Oregon which I suspect is the male of this species although the red on the sides of the abdomen is much more extensive than I have observed in any female (see Philip, 1936) involving the first four tergites and most of the venter, the rows of pale spots only suggested as a pale pollinosity in this sex.

Photography is rapidly gaining in importance for record and descriptive purposes in scientific work. A good, clear photograph will convey much more to the reader of a text than pages of descriptive mattter. Until recent years drawings have held priority as illustrative material, and perhaps still do, but with the rapid advance of photography photographs are assuming a leading role.

Eulia mariana Fern. was identified in Annapolis Valley orchards about twelve years ago and since has become one of the major orchard pests. Although outbreaks continue to occur, fruit growers should fully appreciate the value of natural control, which in one form or another is always assisting in keeping this insect in check. The various natural control factors may be recorded as follows:

(1) Mortality of pupae. (2) Parasites of larvae and pupae. (3) Parasites of eggs. (4) Predators.

The species description presented is based on specimens taken by E. R. Tinkham from the long-billed curlew (Numenius americanus Wils.) collected at Presidio, Texas, May 26, 1929. The specimens are a part of the University of Minnesota collection which has been loaned to the writer for study and identification during the past few years. I am deeply indebted to Prof. C. E. Mickel for his kindness in regard to the loans from the Minnesota collections.

The species considered below are those which are listed in Leiodes in the Leng Catalogue of Coleoptera and which were treated under the name Liodes by Horn (1880, Trans. Am. Ent. Soc. VIII, 296). Since the appearance of Horn's synopsis, they have been neglected, and only one species, interstrialis Hatch, has been described. In the following synopsis, three species are described as new, several changes in nomenclature are suggested, and a number of important characters not noted by Horn are described.

Male (type) resembles H. ziziae (Rob.), to which it runs in my table and that of Metz (but in Lovell's table to modestus), differing however as follows: lateral face marks obliquely truncate above, the highest point next to orbit; flagellum considerably longer, pale dusky reddish (instead of bright ferruginous) beneath; tegulae entirely black; base of wings not pale; thorax more robust, light marks on collar separated by an interval greater than the length of one; wings larger, grey, with the stigma and nervures very dark; abdomen shining pure black (compared with an Illinois specimen from Robertson.).

Male. Length 2.2 mm. Second and third antennal segments equal in length. Punctures of the pronotum evident, those of the elytral intervals very indistinct. Metasternum very indistinctly alutaceous near the lateral margin; the punctures fine and close at middle except on the impunctate area, a trifle coarser on the sides and there distinct but not deeply impressed, very closely placed, the punctures of the anterior margin like those of the disk. Each abdominal segment finely and closely punctate, without coarser punctures on the basal margin.

A species of medium size, elongate-oval, sub-parallel, piceous to rufo-testaccous, usually aenescent. Head large. Antennae and palpi rufo-testaceous, slightly infuscate; clypeus, and labrum anteriorly, rufo-testaceous; two spots on the head rufous; pronotum and elytra with the side margins diffusedly rufo-testaceous in their anterior halves; elytra without pale spots; tarsi, tibiae and femora rufo-testaceous, sometimes clouded with piceous medially, the hind legs darker than the anterior pair. Abdominal sternites three, four and five paler posteriorly.

Male. Very similar to serraticoris Lint., but on the whole more contrastingly marked on the forewings, the light purplish-gray color being replaced by a whitish gray, heavily suffused with smoky; t. a. and t. p. lines poorly defined, much as in serraticornis, the former showing the usual sharp angle, outlined by a dark streak, above vein I and the latter in this same area with the usual small dark patch, closely approached to t. a. line and separated from it by a palish area. Rather heavy blackish suffusion in median area along inner margin.

Since 1930 a study has been made of the lepidopterous stem borers and leaf rollers breeding on deciduous fruit trees as well as on uncultivated plants in or near orchards which have served as sites for Oriental fruit worm parasite liberations. Parasites of these lepidopterous larvae have been reared as an important phase of the study. The objects of these studies include a record of the Microlepidoptera and their hosts and parasites, and possible alternate hosts of introduced parasites of the Oriental fruit worm.

While stationed at the Dominion Biological Laboratory at Cultus Lake, B. C., and conducting investigations on the sockeye salmon, Dr. W. E. Ricker spent some of his leisure time in collecting certain groups of aquatic insects and has generously presented the bulk of the material to the Royal Ontario Museum of Zoology. The Odonata, which were kindly sent to the writer, were collected in a most discriminating manner and include some interesting species hitherto unknown to the region. One new species, a Macromia, is described herewith, while the collection as a whole will be reported upon in a future paper.