NErXUNEA. lit 



Hra&a, Martyn, from the same localities, N. arthritica^Yaii. (tigs. 

 2(j2, 2(54), N. Jndhacea or bulbosa, Yal, (figs. 265, ^i\C>), whicli is 

 evidently the same as arfhritica, Fiisus saturus, Martyn (fig. 2(57). 

 To these I mnst add N. Ginningii, Crosse (tig. 268), from N. 

 China. 



Fusus tornaius, Gonld (fig. 261), from codfish at the Banl<. 

 Fisheries is eqnivalent to the typical despecfa. 



So variable is this species that I doubt the distinctness of even 

 such diverse forms as N. lif^ata, Martyn, and Sijjhonalia Kellettii, 

 Forbes, as well as of Volutopsis Behr-ingii^ Midd. 



N. LIRATA, Martyn. PI. 48, figs. 269-272. 



Shell light brown, encircled on the body-whorl by nine to fifteen 

 revolving ribs, which are not fiattened on the top, usually three 

 of these ribs are visible on tlie spire whorls. 



Length, 3-6 inches. 



N. W. Coast of America. 



Animal whitish, black-spotted ; end of siphon and proboscis 

 black. 



Varies b}' the pra'tial or entire suppression of the ribs as shown 

 by figures 270-272, and then approaches smooth varieties of TV. 

 despecfa. The question of identity of this and the following 

 species has been carefully discussed by Mr. W. H. Dall,* who 

 gives a table of difierences in ornamentation and dimensions 

 founded upon the examination of numerous specimens. Mr. 

 Dall remarks that " it should be remembered that lirata does not 

 occur on the Arctic shores of North America, and the two species 

 are separated by a \'ast expanse of water. Some of the characters 

 in the comparative table graduate towards each other in excep- 

 tional cases, but the sum of the characters is always sufficient 

 to discriminate between the two, and this is all that can be 

 expected between any two nearly allied forms. I regard the two 

 as perfectly distinct." My material is not so abundant as that 

 on which Mr. Dall bases his conclusions, and the differences are 

 not so great. If it be true that neither species exists on the 

 Arctic Coast, it would have to be proven that they did not exist 

 there at some previous period of the world's history in order to 



* Am. Jour. Conch., VII, 108. 



