232 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.54. 



BOREOTROPHON XESTRA, new species. 



Shell fusiform with about six moderately rounded whorls, white 

 with a thin chalky external layer, and distinct suture; last whorl 

 axially sculptured with sixteen sharp elevated laminae, continuous 

 over the whorl but obsolete on the canal, and rising in a short tri- 

 angular spine at the shoulder ; there are also rather strong axial lines 

 of growth irregularly distributed ; there is no spiral sculpture ; aper- 

 ture rounded, outer lip sharp, slightly expanded, inner lip smooth, 

 white, with a thin layer of enamel; pillar obliquely truncate at the 

 proximal end of the canal; canal narrow, long, arcuate, slightly re- 

 curved. Length of shell 34 ; of last whorl 27 ; of canal and aperture 

 20 ; maximum diameter of last whorl 19 mm. 



Hahitat—Stntion 4813 of U. S. S. Albatross, in 200 fathoms, mud 

 and sand, off Sado Island, Japan, bottom temperature 33°. 9 Fahren- 

 heit. U. S. Nat Mus. Cat. No. 205508. Also at Sagami, Japan, 

 Hirase collection. 



This belongs to the group of B. cepula Sowerby, than which it is 

 more delicate, with a longer spire and generally thinner shell. The 

 Hirase specimens were immature. 



BOREOTROPHON ECHINUS, new species. 



Shell thin, yellowish white, fusiform, with about six post-nuclear 

 whorls; nucleus small, smooth, with about two laxly coiled whorls; 

 subsequent whorls spirally sculptured with from one to three strong, 

 rather distant cords, the posterior cord being at the shoulder of 

 the whorl; on the last whorl there may be five to eight of these 

 cords, those on the canal being more or less obscure; at their inter- 

 section with the varices these cords develop guttered spines, usually 

 only the spine on the posterior cord at the shoulder is prominent 

 and this in a well developed specimen may be long and deeply 

 recurved, even sickle-shaped, while in less well developed specimens 

 there may be only an ordinary triangular anteriorly grooved short 

 spine; the slope between the shoulder and the suture behind it has 

 no spiral sculpture; axial sculpture of thin sharp varices varying 

 from ten to seven, less numerous on the later whorls and more or 

 less spinose at the intersections with the cords; aperture sublunate, 

 outer lip sharp, thin, slightly expanded; canal rather long, some- 

 times bifurcated by the end of the previously formed canal, rather 

 tortuous, narrow, and recurved ; inner lip concavely arcuate, smooth. 

 Length of shell 36; of last whorl 30; of aperture and canal 22; 

 maximum diameter (excluding spines) 13 mm. Another specimen 

 is about one-third longer. 



Habitat. — Sagami, Japan. Hirase collection. Cotype, U. S. Nat. 

 Mus. Cat. No. 274076. 



