THE NAUTILUS. 101 



continent to another, intentionally or accidentally, with plants, seeds, 

 ballast, etc. A rather large number of species have come over from 

 Europe to this country, and there is no doubt that the process will 

 go on. 



SHELLS FBOM THE BAY OF CADIZ REGION 



BY MAXWELL SMITH. 



(Concluded from p. 83.) 



Cassis saburon Brug. Cassis undulata Gmel. 



Morio echinophora L. 



Dolium sp. Said by the fisherman to live in vast numbers in the 

 bay. 



Amphiperas spelta L. Three in drift. 



Cypraea achatidea Gray. One from a fisherman. Said to have 

 been taken here. The species I have represented in my collection 

 from Sicily and Oran on the Algerian coast. 



Cypraea pyrum. Mrs. Whishaw, several. 



Trivia europea Mont. A few examples. 



Erato laevis Donov. A few fine and many dead in drift. Prob- 

 ably lives nearby in deep water. 



Chenopus pespelicani L. Mrs. Whishaw. Small form. 



Triforis perversus L. Mostly young shells. 



Cerithium rupestris Risso. 



Cerithium vulgatum Brug. Probably living. 



Bittium reticulatum Costa. The most plentiful species taken. 



Vermetus subcancellatus Biv. One, worn. 



Turitella communis Risso. Several. 



Littorina clathratus Phil. Littorina neritoides Phil. 



Littorina punctata Gmel. 



Rissoa cimex L. Some with deep brown bands. 



Rissoa lactea Mich. Pure white, a beautiful species. 



Rissoa ventricosa Desh. The most abundant Rissoa. 



Truncatella truncatuhi Mull. In drift. 



Paludestrina acuta Drap. Common in drift. Undoubtedly also 

 lives near. 



Calyptraea sinensis L. Mrs. W. 



