694 Modification of the Apex in Gastropod Mollusks. 



dead white. The young shell from the egg (fig. 30) is large, 

 sinistral, the nucleus is large and knob-shaped, and the second 

 whorl is nodulous and strongly shouldered. It is also spirally 

 striate, strongly costate, and marked with reddish flames as in 

 the adult. The interior of the outer lip is strongly striate. This 

 apex differs from the others in the genus by the presence of the 

 ribs, shoulder and color, in the other species these appear first on 

 the post-nuclear whorls, instead of the nuclear as in this species. 



Fulgur canaliculatus Say. (Fig. 31.) 



The apex of this species is very like that of Fulgur pyrum (fig. 

 27) ; the present nucleus, however, is a little more rounded, and 

 the first whorl is more knob-shaped and the initial point deeply 

 buried in the second whorl (there are one and a-half nuclear 

 whorls). The second whorl is faintly shouldered and the first 

 post-nuclear whorl is heavily shouldered, and the latter is strongly 

 nodulous. In color the apex is white, and it is also smooth. 

 About a dozen specimens examined. 



Family BUCCINIDiE. 

 Genus CHRYSODOJfllJS Swainson. 



Cbrysodomus antiquum Linne. (Figs. 32, 33.) 



Apex of good size, rounded, smooth (?), consisting of two and 

 a-half whorls, slowly and regularly increasing in size ; the nuclear 

 whorls are (apparently) smooth, and the post-nuclear whorls are 

 spirally striate and shouldered. The apex is yellowish white in 

 color. The specimens of typical antiquus before the writer have 

 almost been ruined by acid, so that the nucleus, while showing 

 perfectly the original form, is yet devoid of all markings. In a 

 specimen of contraria Linne {=^ antiquus) (fig. 33), the nuclear 

 whorls are encircled by five strong spiral lines. The apex of this 

 form differs from the typical antiquus in being more discoidal and 

 oblique. The writer is convinced that antiquus (typical) is stri- 

 ated precisely as in contraria. Dealers' shells are of but very 

 little value, scientifically. 



Genus PISANIA Bivona. 



Pisania pusio Linne. (Fig. 34.) 



Apex small, rounded, smooth, consisting of one and a-half 

 glossy whorls, regularly increasing; the post-nuclear whorls 



