ARGON AUTA. 



Plate II. 



Species 2. (Mus. Cuming;.) 



Argonauta Aego. Arg. testa transverse involuta, late- 

 ralis modice convexis, versus carinam anguste contrac- 

 tu, rugis gracilibus, Itevibtis, continuis ; carina angusta, 

 tuberculis parvis, numerosis, approximatis ; auriculis 

 contracts. 



The Argo Argonaut. Shell transversely involute, with 

 the sides moderately convex, narrowly contracted to- 

 wards the keel, wrinkles slender, smooth, continuous ; 

 keel narrow, tubercles small, numerous, approximate ; 

 auricles contracted. 



LiNNiEUS, Syst. Nat. (Gmel. edit.) p. 336. 



Cymbium maximum, Gualtierri. 



Argonauta maxima, De Blainville. 



Testa juvenis. Argonauta haustrum, Dillwyn. 



Hab. Indian, Pacific, and Atlantic Oceans. Mediterra- 

 nean. 



It will be seen by the foregoing synonymy that the 

 colossal Indian Ocean Argonauta Argo, figured in the ac- 

 companying Plate, has been described as a species distinct 

 from the original type of smaller dimensions inhabiting 

 the Mediterranean. But this opinion has not been gene- 

 rally received. The truth appears to be that the animal to 

 which this shell belongs is almost ubiquitous in its distri- 

 bution, at least within forty degrees of either side of the 

 Equator ; and the shell, varying in size and general out- 

 line, retains all its specific characters in detail. The large 

 specimen here represented was collected by Mr. Cumiug, 

 at the Philippine Islands, the specimen given in Plate III. 

 Fig. 2 c, was taken at Venezuela, Central America, and 

 that at Fig. 2 d, at Tahiti, both of which varieties come 

 very near indeed to the well-known Mediterranean form 

 of the species. 



April, 1861. 



