In the course of a comprehensive study of insects frequenting dwellings, attention was early drawn to a very handsome little Collembolan, which occurs commonly in moist situations in houses in Washington. It may often be found on window-sills, especially if there is unusual moisture from the presence of window plants, or in bathrooms, and, in fact, whereever moist conditions prevail. This species is a very handsome one, and seems, from reference to the authorities, to be undescribed. From thé manner of its holding the head, bent downwards almost at right-angles to the thorax, it would seem to fall into the genus Lepidocyrtus, erected by Sir John Lubbock. In habit it has in Europe a close ally in Seira domestica, Nicolet, which, as its name implies, is a frequenter of houses, and is separated generically from Lepidocyrtus by rather unimportant characters.

Aphilanthops concinnulus, n. sp. — ♀. Length, 9 mm. Rufous, with white markings, a rather obscure broad black band extending across vertex, including most of the ocelli, its lower margin concave, mandibles darkened towards tips, mid and hind tarsi darkened. The white or yellowish-white marks consist of a small spot on each lower corner of face, a small obscure suffused spot on mandibles near base, the prothorax above, the tegulæ except extreme base, the tubercles, a large patch behind tubercles having a linear oblique projection above, the anterior margin of scutellum, a spot on each side, the postscutellum, spots at the apices of anterior and hind femora, longitudinal bands on all the tibiæ, a large patch on each side of the first three abdominal segments, a band on the fourth, a broad quadrate spot medially on the fifth. Venter immaculate. Face with the usual silvery appressed pile. General structure, wings, etc., as in quadrinotatus, but the third submarginal cell is much less produced at its apex, and the third at its base, than in quadriuotatus, this character, however, being liable to variation. The anterior tarsi present numerous gray spatulate hairs. The apex of the abdomen is of the same type as in quadrinotatus.

In Europe and in New Zealand species of the genus Ripersia have been found, which lived in the nests of certain ants. It had always seemed to me singular that nothing of the kind should occur in this country; but Mr. G. B. King has proved that they merely wanted looking for, his researches in Massachusetts having led to the discovery of three species, here briefly described.

Eyes bare, arista plumose, scutellum with long hairs on the margin, third antennal joint very large, bright yellowish-red. Legs black.

Male.—Front prominent, opaque, strongly sulcate medially, very indistinctly punctulate, long black pilose. Face shining black, pollinose on the sides and pilose on orbital margin below; below the antennæ deeply concave to the tip of the tubercle, thence gently concave to the epistoma. Tubercle projecting somewhat beyond the base of the third antennal joint, round. Cheeks shining, sparsely whitish pilose. Ocellar area black pilose.

Belonging to Division II., group two of the genus as given in my Preliminary Studies. Nearest sciurorum.

Head without combs of spines, in the female normal, highest at the occiput, gradually sloping forward, then rapidly curved in front, anterior edge of face nearly perpendicular, but rounded; head in male flat above or slightly concave, strongly rounded in front, the anterior edge of the face slightly receding. Bristles on head few, these being on both sides of the antennal groove and on the occiput. Antennal groove open, bristles on joint 2 short. Mandibles equalling or slightly exceeding the fore coxæ. Pronotal comb of twenty-two spines.

Two flies have emerged from cocoons which had passed two winters. Last summer I noticed an example of mistaken instinct. The eggs of this species are laid under the lower epidermis by saw-cuts in the edge of the leaf. Several eggs so laid were found on Ilex verticillata. In due time the larvæ hatched, but refused their food, and would undoubtedly have perished had I not recognized them and supplied them with willow, which they attacked voraciously.

In 1895, according to Mr. A. R. Grote, “the European type of Agronama seems certainly to be vestigiatis.” This species was declared to be congeneric with the American species classed by me as Feltia, and the latter genus was dropped in favor of Agronoma, and Mr. Slingerland was scolded because he had adopted the generic name used by me. In the January (1896) number of the Can. Ent. I pointed out for Mr. Grote's benefit, and also for the information of American students, that there existed certain points of structural difference which had escaped Mr. Grote's examination, which made the declared type of Agronoma a member of the genus Agrotis as restricted by me, the latter genus being based upon the very species which Mr. Grote said was its type. As the result of this paper, it has become much less “certain” to Mr. Grote's mind that vestigialis is, after all, the type of Agronoma, and on reconsidering the matter, it seems to him that crassa had better be considered the type.