56 



edition, from the Proc. Acad. Nat. Sci., I will not repeat them here. See 



Index. — ^Ed.] 



Planorbis glabratus, Paludina, 



lymn.a:a columella, " limosa, 



CyCLOSTEJIA, ' ' LAPIDARLA., 



' ' TKICARINATA, AlASMODOSTA, 



AnCTLUS, " MAKGINATA, 



'♦ RrvuLAEis, Cyrena, 



CyRENA CAROLnOENSIS, Bosc. 



[No. 2. From the Philosophical Transactions of the Royal Society, 

 1819, p. 107.] 



On the Genus OCYTHOE ; beiiiff an extract of a letter from 



Thonias Say, Esq., of PMladelpTiia, to Wm. Elford Leach, 



M. D., F. R. S. 



I have before me a specimen of Ocythoe in an Argonauta, form- 

 ing part of the collection of the Acad. Nat. Sciences. It was 

 taken from the stomach of a dolphin, which was caught in sound- 

 ings on our Atlantic coast, and is in the most perfect state of pre- 

 servation, not having suffered the slightest decomposition from 

 gastric action. 



It is sufficiently distinct from your 0. Cranchn, as well as from 

 the animal of Naiitihis sulcatus of Klein ; and if the figure given 

 by Shaw of the animal of Argonauta argo has any pretensions 

 to accuracy, it is most probably an unknown species. 



I here attempt a description of it, and also submit a few remarks 

 on the genus : 



Ocythoe punctata. — Body pale, punctured with purplish; 

 abdomen conic-compressed, vertical, semifasciate near the sum- 

 mit, with a profoundly indented transverse line ; arms much longer 

 than the body, attenuated, filiform at their tips, alated ; membranes 

 rounded. 



Inhabits the Atlantic Ocean near the North American coast. 



Descrij). Abdomen conical, slightly compressed, nearly vertical 

 with respect to the disk of the head, with a profoundly indented 

 transverse line, which extends half round, near the summit. Arms 

 attenuated, much longer than the body, filiform towards the tip, 

 slightly varied with brassy, inferior ones when extended double 

 the length of the body; suckers alternate, becoming gradually 

 smaller towards the extremities of the arms, where they are very 



