OF CONCHOLOGY. 139 



with a narrow umbilicus. The shape of the pinnae differs in the 

 two. 



Habitat. — Monterey, Gala., dead on beach, Dall, 1866. Neah 

 Bay, W. T. Swan. Off the Peninsula of Aliaska, living, 1865, 

 Dall. 



It is worth note that no Pteropods appear, after several years 

 exploration, to inhabit Bering Sea. I found none north of the 

 Aleutian Islands, though they were common enough to the south- 

 ward of them. I took several quarts in a disorganized condition 

 from the stomach of a specimen of Orthagoriscus analis, Ayres. 



Family CLIONID^]. 



(JLIONE, Pallas. 

 CLIONE ELEUANTISSIMA, 11. S. 



Pinnae small, pink, with translucent margins, a ray of bright 

 crimson in the center of each, sub triangular. Body pyriform, 

 slender caudal end usually curved to one side ; a patch of 

 brownish crimson with well defined edges, on the back, ventral 

 side and tail, brownish pink. Head well differentiated, longi- 

 tudinally striped with carmine on a lighter ground. Tentacles 

 two, short, cylindrical, brownish. Cephalic lobes six, thick, 

 leaf-like, short, covered with fine granulations or pores on their 

 anterior sides, which are flattened and of the most brilliant car- 

 mine. Disk cleft in the median line. Mouth with two broad 

 carmine labia. 



Length, "28 ; breadth of pinnae, "22 in. 



#a^a£.— Pacific Ocean, in lat. 51° 50', Ion. 101° 26'. Au- 

 gust 2, 1866, Coll. reg. No. 309, W. H. Dall. 



This exquisite little species is smaller and more brightly col- 

 ored than any other yet described. It also differs in form from 

 any other. In this and other species the notes on the color, &c, 

 were taken from life. 



PNEUMODEMID^E. 



PNEUMODERMON, Cuvier. 

 Pneumodermon Pacificism, n. s. 



Body subcylindrical, elongated, rounded behind, livid purple. 

 Pinnae subquadrate, arched at their inner anterior margin, deeply 

 notched at their inner posterior edge. Anterior margin with a 

 well marked band of white ; remainder dull purple, lighter be- 

 hind. Head indistinct, cylindrical. Oral aperture deeply 



