320 REPORT ON ALBATROSS MOLLUSCA DALL. 



FAMILY BUCCINLELE. 



Genus BUCCINUM Linne". 



Buccinum viridum sp. nov. 



Plate vi, Fig. 9. 



Shell delicate, thin, inflated, six-whorled,with a delicate greenish gray, 

 slightly fringed, dehiscent epidermis; spiral sculpture of numerous sub- 

 equal flattish threads, with narrower rounded interspaces and no inter- 

 calary threads; these threads are, as usual, slightly coarser on the base 

 and finer behind the shoulder of the whorl near the suture; at the 

 shoulder a single more prominent but not much larger thread slightly 

 turriculates the spire; whorls full and rounded, especially on the base; 

 suture distinct but not channeled ; aperture wide, outer lip somewhat 

 patulous in front, receding toward the suture; canal wide, short, hardly 

 discriminated from the aperture, very slightly recurved; fasciole dis- 

 tinct but not prominent; pillar thin, twisted; inner lip smooth, white, 

 slightly excavated, or the limy outer layer of the shell is there absorbed 

 and the space covered with a thin wash of polished glaze ; except for 

 the epidermis the shell is pure white. The outer lip is very thin and 

 but slightly reflected. The nucleus is eroded on the surface so that its 

 character is not determinable. Maximum longitude of shell, 46,; of 

 aperture, 24 ; maximum latitude of shell, 29 mm . 



Hab. — Station 2839, off Santa Barbara Islands, California, in 414 

 fathoms, sand. 



The operculum is oval, slightly pointed towards the extremities, thin 

 and normal, the nucleus being near the margin about three-eighths of 

 the distance from one end toward the other. The soft parts are whitish, 

 the tentacles moderate, the swelling for the eye present, but usually 

 uupigmented, though a trace of the color seems to remain in some 

 specimens. The gills and osphradium are as usual. The verge is as 

 long as the foot, stout, geniculate, razor-blade shaped, the thin edge 

 being to the right or when recurved and turned under, as is generally 

 the case, to the left ; the distal end is squarish, rounded at the corners, 

 the thicker angle terminating with a small acorn-shaped papilla. The 

 dentition recalls that of B. undatum, but the central tooth has five sharp, 

 spike-shaped, subequal denticles, the two iuuer cusps of the laterals, 

 while smaller than the outer cusp, are more nearly its size, the middle 

 one of the three tends to be smaller and to have one or even two mi- 

 nute denticles, one on each side in the latter case, near its base. The 

 formula would be J.^J and the full formula of a fully developed lateral 

 would be i+F 1 . None of the specimens were fully mature, though the 

 one figured had formed the beginniug of the reflected lip, so that its 

 shape could be ascertained ; but it is probable that fully mature speci- 

 mens would have the reflection wider and stronger. 



