I define this new genus with great hesitation and doubt as to the propriety of so doing. The only reason for separating the species described below, and which I place in this genus, from Evippe (vid. E. prunifoliella, ante v. 5, p.185) is found in the neuration. The other characters are those of Evippe, and, as stated below, it is very near to E. prunifoliella in ornamentation. The neuration of the forewings is exactly that of Eidothea vagatioella (loc. cit. sup.p. 187), which it also resembles in ornamentation, but less closely than it does Evippe prunifoliella.

Head, thorax, abdomen and wings above, of a creamy white, without any trace of bands or markings. Beneath, the body and wings are also creamy white, the costa of both fore and hind wings being near the base very faintly tinged rvith yellowish pink. The legs are also slightly pinkish. Antennae pale brown. Palpi and other parts of the mouth yellowish.

Since I am recently criticized for erecting new genera in the Sphingidæ as it is thought unnecessarily, I have put together some of my thoughts on the subject in the present Paper. In a review, the friendly spirit of which I most gladly recognize, Mr. Moschler speaks of my division of the old genus Smerinthus, which I have restrictcd to the type ocellatus, geminatus, &c.,and says in effect that since hybrids are known to occur between certain of the species, these could not be generically or tribally separated.

This species, collected by Mr. G. H. Belfrage, in Bosque Co., Texas, Sept. 16th, differs from T. chrysellus by the broader, more olivaceous basal and median fasciae, narrowly united along the hind margin of the wing. The white fields of the primaries are thus less extended than in its congener. Subterminal line diffusely shaded with olivaceous, as is the terminal margin, leaving a whitish apical space. . Fringes whitish, thorax light olivaceous. Hind wings less purely white, with a terminal olivaceous shading.