Tetracanthella pacifica sp. n. from Coastal British Columbia is described and illustrated. A key to the Nearctic Tetracanthella species is given.

Male.—Length, 10.5 mm. Black with yellowish markings. Head transverse, as wide as thorax, about twice as wide as long when viewed from above; face above the antennæ, and vertex, polished, impunctate, without apparent sutures and with sparse blackish pubescence; the cheeks and under surface with pubescence more dense; clypeus polished; palpi slender; antennæ as long as head and thorax, rather stout, eighteen-jointed, segments subequal; eyes small but prominent; ocelli small, in a triangle on a line with the posterior margins of the eyes. Thorax rugose with coarse, irregular punctures, those of the pleura and pectus smaller and more numerous; posterior angles of prothorax yellow; legs rather slender, coxa and femora black, remainder yellow, the tips of tibiæ and tarsi somewhat dusky; wings subhyaline, with dark stain covering marginal cell and extending slightly beyond each end of it, stigma and costal nervures black, remaining nervures reddish, second and third submarginal cells subequal; scutellunl abruptly rounded posteriorly, postscutellum yellow, prominent, subpyramidal, notched at apex, in suture on each side several deep shining foveæ; metathorax very short and rounded at sides, without prominent angles, a small yellow spot on each side. Abdomen polished, impunctate, apparently with six segments; second segment as long as all the following and with a yellow central band, or elongated spot on each side; a yellowish spot at lateral base of segments 3 and 4, very faint on the latter; venter slightly pubescent, with double row of yellow spots on segments 1 to 5, largest on 2nd.

The Pyralid genus Dichogama has not yet been reported from United States territory on the mainland, but at least three species occur in southern Florida. The following notes were made on the larva of one of them, D. Redtenbacheri.

Stage II. (?)—Head flat before clypeus high, mouth pointed; luteous, ocelli black; width .4 mm. Body a little flattened, translucent, yellowish, a geminate lateral brown stripe. Cervical shield large, colourless, brown dotted on the tubercles and on lateral edge; anal plate small, not marked. Tubercles small, brown; setæ long, stiff, pale. Skin sparsely granular; segments scarcely annulate.

In a previous paper (16) an account was given of the relative efficiency of dry deposits of Diazinon [0,0-diethyl 0-(2 isopropyl-4-methyl-6-pyrimidyl) phosphorodithioate], Trithion [0,0-diethyl S-(p-chlorophenylthiomethyl) phosphorodithioate] and Sevin[l-naphthyl N-methylcarbarnate] in preventing the reinfestation of apple trees by the apple aphid, Aphis pomi DeG. In those experiments no comparison was made of the initial effectiveness of the insecticides in killing aphids by direct contact while the spray deposits were still liquid. Instead, interest was concentrated on the relative progress of recolonization of aphid-free trees, by aphids, as a measure of the effectiveness of dried and aging deposits. In the work reported here the results of similar investigations on two further aphicides are described.

The mature larvae of three species of Hoplitis, namely Hoplitis anceyi (Pérez), Hoplitis anthodemnion Michener, and Hoplitis nitidula (Morawitz), are described and compared with the other known larvae in the genus. The morphology of the spiracles, antennal discs, and antennal papillae, the absence of a seta on the mandibular basis, and the shape of the vertex permit the characterization of each species. Furthermore, H. anthodemnion has the integument covered by setiform spicules. Nevertheless, there is no clear separation between the three species studied and those previously known, and larval morphology does not support the consideration of Anthocopa and Hoplitis as separate genera.

Dactynotus nodulus is described and illustrated and its affinities noted.

The purpose of the present paper is to describe two new species of Bolbocerosoma and to figure the genitalia of the North American species of this genus. It therefore supplements the paper of Dawson and McColloch (Can. Ent., LVI, 9-15).

Regression models of the form lnY = b0 + b1ln(X−c) + b2X are presented that describe the within-tree distribution of the pupae of Thanasimus dubius (F.), a clerid predator of the southern pine beetle, Dendroctonus frontalis Zimm. More T. dubius pupae/100 cm2 of bark area were found in loblolly pine, Pinus taeda L., than in shortleaf pine, P. echinata Miller, and the number increased with increasing tree diameter class. Peak densities were found at a height of 1–4 m.

All of the species described in the following pages belong to genera which are of small extent or have been recently monographed, and it is hoped that no confusion will result from their publication. The types are in my own collection, and unless otherwise credited, were captured by myself.

In September, 1873, Mr. T. L. Mead, who was then at Coalburgh, observed a ♀ pseudargiolus depositing eggs upon the flowers of Actinomeris squarrosa, and on examining the flower heads found a number of eggs. He brought home two of the females, and enclosed them in a muslin bag upon the flower heads of the same plant, near my house, the plant being not at all an uncommon one here. Several eggs were soon deposited, and in due time the larvae were hatched and some of them were carried through to chrysalids, a change which occurred about the middle of October.

Eulecanium fraxini, n. sp.–Adult ♀ scale 6 mm. long, 5 broad,2 high; some individuals are practically circular in outline and variable in size. In July the scales are well covered with a grayish powdery secretion; this being removed they are reddish brown, considerably wrinkled and pitted, surface shiny, texture thick.

Boiled in potash the derm becomes very clear and transparent, showing some large gland-pits 24 μ in diameter. Mouth-parts, legs and anal plates tinged with yellow.

Hypothyce mixta, a new genus and species from eastern Texas is described and compared with the related genera Thyce LeConte, Plectrodes Horn, Dinacoma Casey, and Hypotrichia LeConte. A key to the genera of Melolonthini of America north of Mexico is included and the genus Hypotrichia is transferred from the Liparetrini to the Melolonthini.

Periclista, Knw.—This name was proposed by Knonow in his monograph of the European Blenocampids, published in the “Winer Ent. Zeit.,” V. 1886, 186, for those species having the lanceolate cell petiolate, the eyes more or less remote from the bases of the mandibles, and the posterior wings with the outer cells closed by a marginal vein. This name had already been used by Forester, 1869, tor a genus of Cynipidæ, and I therefore propose the name Mogerus (μογερός) to take its place.

Oligotrophus papyriferae Gagné is univoltine in Michigan. Adults emerge in mid-May and the females deposit small egg clusters on the underside of the leaf near the petiole of paper birch (Betula papyrifera Marsh.). Larval eclosion occurs 1–2 weeks later; there are three instars. The larvae bore into and down the petiole and enter the stem or a bud attending the leaf base. Galls appear in early August. There are petiole-bud and petiole-stem galls, depending on which tissues are infested. Third-instar larvae vacate the galls in late September, work their way into the litter, and construct cocoons in which they overwinter. Pupation occurs the following May. Trees from 2 to 30 ft tall are attacked; lower branches are attacked the heaviest. Large galls kill buds, twigs, and entire branches. Small galls leave deeply indented branch scars and deformed limbs.

In the routine work of sorting and determining Aquatic Hemiptera from the western United States, I was quite surprised recently to discover two new species in genera which I supposed were fully known. In a lot consisting of 110 Ranatra tahen by Doctor R. H. Beamer and his parties on the Biological Survey trips into the southwestern United States during the last two or three years I found one specimen of a very distinct and new species.