UROSALPINX. 151 



P. PROPINQUA, Tenison- Woods. 



u This shell so closely resembles P. littorinoides, that no better 

 description can be given than to say that it is broader, shorter, 

 with fewer whorls, and the spiral lira 1 become six stout corrugated 

 ribs with a corrugated one at the angle. The aperture is fulvous. 

 It is intermediate between the species just mentioned, and Mr. 

 Angas ? P. Flinderxi. The difference may be due to climate. 

 Future observers must solve the question of the specific distinc- 

 tion of these three shells which are different enough at their 

 various stations, many hundred miles apart, but may possibly 

 graduate one into another as they are traced north or south. 



" Length 13, diam. 8 mill." 



N. W. Coast Australia ; extremely abundant on rocks at low water. 



T. GYBATUS, Hinds. PI. 33, fig. 3f)2. 



Brownish white. Length, '75 inch. 



Straits of Macassar ; in coarse sand, 17 fms. 



Described as a Trophon, and by Reeve and Kobelt placed in 

 Murex. I figure it here, but think it may prove a young Siphon- 

 alia. Operculum unknown. 



T. UNICARINATUS, Phil. 



Shell minute, violaceous, oblong-fusiform, smooth ; whorls 

 carinate above, forming a shoulder ; canal open, equaling and 

 confluent with the aperture. Length, 3*5 lines. 



Straits of Magellan. 



This may possibly be the young of one of the numerous 

 varieties of T. Geversianus. It was described as a Fusm, which 

 of course it is not. Not figured. 



Genus UROSALPINX, Stimpson. 



Shell elongated oval, or short fusiform, longitudinally ribbed 

 or undulated and spirally striated ; aperture with a short canal ; 

 outer lip dentate and lirate within. Operculum somewhat like 

 that of Purpura, semicordate, with the nucleus at the outer edge 

 a little below the middle. Lingual dentition nearly like that of 

 Trophon, the lateral teeth having an elongated base of attachment ; 

 but the rhachidian tooth has numerous minute denticles between 

 the principal ones, corresponding to ridges on the surface of the 



