Perkins.] 116 [October 6, 



Common on shore dead. Laminarian. In most cases it is not 

 banded, and is often covered with a greenish black coating. Animal 

 dusky; rostrum long, cylindrical, recurved over the shell; tentacles 

 slender, with the eyes on the outer side a third of the distance above 

 the base ; above the eyes the tentacles become abruptly smaller ; 

 foot large, ovate, auricled in front and round pointed and notched 

 behind, with a tentacular process on each side ; lingual ribbon rather 

 short. Teeth 1-1-1 ; median tooth arched, bearing nine sharp, slender 

 denticles, the central being longest ; lateral teeth short, broad, claw- 

 shaped, with two denticles. 





MEASUREMENTS. 



engt 



i of shell 17.4 mill. Breadth 8.6 mill. 



a 



foot 10.6 " " 7 " 



u 



tentacles 5 " " 1.2 " 



at base. 

 Ilyanassa Stimpson, 1865. 



Ilyanassa obsoleta Stimps., Am. Journ. Conch., Vol. i, p. 60, 

 pi. ix, figs. 11, 12. Nassa obsoleta Say, Am. Conch., p. 77, 1822. 

 Buccinum obsoletum Gould, Invert. Mass., p. 208; De Kay, Moll. 

 N. Y., p. 133, pi. viii, fig. 163. Buccinum oliviformis Kien., Icon., 

 pt. ii, p. 20, pi. xxv, fig. 99. 



Very abundant, covering large tracts of mud near low water, and 

 washed ashore in great numbers. Animal dark ; proboscis rather long ; 

 tentacles acutely triangular, short, eye spots near the outer base ; 

 foot straight in front, slightly auricled; round pointed behind, 

 white, thickly mottled with black ; operculum small, oval, thin, cor- 

 neous, lines of growth not prominent. Teeth 1-1-1; median much 

 arched, bearing numerous small denticles ; lateral teeth with two 

 denticles, the outer much the larger. 



MEASUREMENTS. 



Length of shell 15.6 mill. Breadth 10.4 mill. 



" foot 16 " ,: 9.2 " 



\ " rostrum 9.4 " 



" tentacles 5 " 



" operculum 3 " " 2.4 " 



Ova capsules small, nearly sessile, oval, flattened ; anterior and up- 

 per surface covered with a coarse network of sharp ridges forming 

 facets of a somewhat quadrangular form, which extend to the edge 

 forming points; posterior side smooth, as is the base; opening near 



