54 THE NAUTILUS. 



NOTES ON THE WEST AMERICAN SPECIES OF FTTSINUS. 



BY WILLIAM H. BALL. 



The genus Fusinus, better known by its preoccupied name of 

 Fusus Lamarck, is fairly well represented by species on the 

 Pacific coast. 



The largest, most conspicuous, and best known of these is F. 

 dupetitthouarsi Kiener, 1840, originally described from a Gala- 

 pagos Island specimen and which has since been collected at a 

 point as far north of Panama on the mainland as Cerros Island 

 in latitude 28. It undergoes no great variation in this wide 

 area of distribution. 



F. kobelti Dall, 1877, has been collected from the vicinity of 

 Monterey and south to Catalina Island. 



F. sulcatus Lamarck, 1822, is found at Panama, and appears 

 to be distinct from F. fontainei Orbigny, 1841, which is a native 

 of Peru and Chile, and of which F. alternatus Philippi, 1847, is 

 a synonym. 



F. colpoicus new species, is found off Guaymas, Gulf of Cali- 

 fornia, and resembles F. barbarensis Trask, when the latter is 

 about 60 mm. long, but differs by having 13 instead of 11 axial 

 ribs, which are narrower and with wider interspaces while the 

 revolving threads are sharper and more conspicuously alternated. 

 At a length of 66 mm. it has eight whorls without counting the 

 eroded nucleus ; three of the spirals near the periphery are 

 more conspicuous than the rest ; at the end of the penultimate 

 whorl there are 6 major and 6 minor spirals which pass over 

 the ribs without becoming nodulous. The aperture and canal 

 together measure 36 mm. in the length, and the canal is con- 

 spicuously tortuous. The maximum diameter of the shell is 

 18mm. (U. S. N. Mus. No. 111,111). 



The peculiar F. (Roperia) roperia Dall, 1898, is still only 

 known by the type specimen from San Pedro ; F. cancellarioides 

 Reeve, 1848, only from the Chilean coast. An unidentified 

 worn shell sent from La Paz by Kantus, seems distinct from the 

 others but is not fit to serve as a basis for a name. 



There is a group of species found in the central Californian 

 region which were described by Trask in 1855. F. Iraski Dall, 



