MUSEUM OF COMPARATIVE ZOOLOGY. 133 



Super-Family RHACHIGLOSSA. 



The connection of this group with the Toxoglossa has been already shown 

 to be intimate, as illustrated by the radula of Spirotropis, at once Toxoglossate 

 and Rhachiglossate. Doubtless the two series should be combined under one 

 head, and thus opposed to the Tsenioglossa. But until more is known, I prefer 

 to leave the nominal arrangement undisturbed. 



Family OLIVIDjE. 



Genus OLIVA Brcgi£re. 



Oliva reticularis Lamarck. 



Oliva reticularis Lam., Ann. du Muse'um, XVI. p. 314. Tryon, Man. Oliva, p. 83, 

 pi. xxx. figs. 90-100, 1-4. 



A fresh specimen was obtained in 73 fms., at Station 290, near Barbados, 

 and a young dead specimen in 54 fms., near the island of Sombrero. 



This beautiful shell lives in the sand, for the most part too deep to be 

 reached by tbe trawl, which may explain their comparative absence from the 

 collection while so common in the region visited. 



Oliva litterata Lamarck. 



Plate XXXIV. Figs. 8 a-o, 8'. 



Oliva litterata Lam., Ann. du Muse'um, XVI. p. 315 ; Say, Am. Conch., III. p. 152, 



1830. 

 Oliva Sayana Ravenel, Cat., p. 19, 1834. 



Fragments occurred in several dredgings, but the specie3 lives in shallow 

 water, on sand fiats. 



Genus OLIVELLA Swainscw. 

 Olivella mutica Sat. 



Plate XXXIV. Figs. 1 a-r, 2. 



Oliva mutica Say, Journ. Acad. Nat. Sci. Phil., II. p. 228, 1822. 

 Olivella zonalis Conrad, Journ. Acad. Nat. Sci. Phil., VII. p. 153, 1834. 



This species occurs in fragments, evidently disgorged by fishes in deep 

 water, but lives only on the shores, in shallow sandy places. 



The animal has the posterior filament to the mantle, like Oliva, but wants 

 eyes and tentacles, while possessing an operculum which is denied to Oliva. 

 According to Stimpson, there does not seem to be any proboscis in Olivella 



