104 PROCEEDINGS OF THE ACADEMY OF [Feb., 



Usilla gouldii (Smith). PI. Ill, fig. 14, 



Planaxis cingulata Gld., Otia Conch., p. 140, not of A. Adams. 

 Planaxis gouldii E. A. Smith, Ann. and Mag. N. H., 1872, IX, p. 42. 



Shell ovate-oblong, thick and solid. On the last whorl there is a 

 subsutural welt followed by a depression, then seven slightly convex 

 girdles separated by narrower spaces, each occupied by a single low 

 cord at and above the periphery, but on the base the spaces are wider, 

 with two or three cortls ; on the spire a microscopic, dense subvertical 

 striation may be seen in unworn specimens. The girdles arc very low, 

 almost flat on the latter part of the last whorl, but more and more 

 raised earlier, two strong ones appearing on the penultimate whorl, 

 where they are somewhat nodose. On the earlier whorls these two 

 girdles and the subsutural welt are set with transversely oblong tuber- 

 cles along weak vertical folds. Siphonal fasciole short and convex. 

 Whorls about 6 J, the tip minutely eroded, the first whorl smooth. 

 Last whorl tapering and a little concave below the slightly swollen 

 peripheral region. Aperture oblique, about three-fifths the total length 

 of the shell, blackish within, with a single peripheral pale line. Ante- 

 rior channel short and deep, posterior sinus narrow and gutter-like, 

 defined by a curved ascending callous cord on the lip and a small 

 callous pad on the body. Outer lip regularly arcuate, thickened 

 within and armed with six teeth in adult shells. Columellar margin 

 dilated, rather wide. Color blackish-brown, with blue spots on some 

 of the spiral girdles, the tubercles on the spire and a few bands in inter- 

 vals on the last whorl being yellowish. Behind the lip all of the inter- 

 vals between the raised girdles become yellowish, terminating in sub- 

 triangular yellow spots on the bevelled lip, seven in number. 



Length 13.2, diam. 7 mm. 



Length 11.7, diam. 6 mm. 



Hahajima, Ogasawara. The specimens described are No. 87,754, 

 A. N. S. P., from No. 1,628 of Mr. Hirase's collection. Gould's types 

 were from Oshima, Osumi. 



This peculiar little whelk has been unfortunate in its biographers. 

 Dr. Gould placed it in a wrong genus and family, and used a preoccu- 

 pied specific name; and Mr. Smith, who renamed it, had not seen a 

 specimen, and left it in the genus Planaxis. Pease, in a note on Usilla 

 fusconigra, alludes to Gould's species as a member of Usilla.^ The 

 species has not been figured hitherto. 



The group Usilla has been considered a subgenus of Vexilla, and 

 located in the Purpnrince. The rather flat columella, and yellowish 



' Amer. Jortrn. of Conrh., IV, 11,5. 



