142 AMERICAN JOURNAL 



evident, as the only character assigned -which distinguishes it 

 from Busycon is the "ribbed" surface. Examination of speci- 

 mens, however, show that the nucleus is depressed helicoid, and 

 the columella straight towards the front : the whorls are longi- 

 tudinally plicated and crossed by revolving ribs. The general 

 form, the whorls being angular and plane behind and ventri- 

 cose below the angle, as well as the marginal columellar fold, 

 nevertheless appear to indicate affinity to FiiJgur. 



It is necessary to remark, in conclusion, that the notation in- 

 dicating the comparative value of Synonyms proposed by 

 Strickland has been adopted ;* that reference has been made 

 only to such authors as have modified the genus or its charac- 

 ters, and that when a specific type has been mentioned, it is in- 

 dicated in parentheses after the reference to the authority. 

 Finally, the laws of nomenclature originally sanctioned by the 

 British and American Associations for the Advancement of Sci- 

 ence have been obeyed, although in some respects repugnant to 

 the views entertained by the author. 



FuLGUR Montfort. 



< Busycon, Bolt, Mus. Bolt, 1798 (undescribed). 



< Busycon, Morch, Cat. Yoldi I., 1852, p. 104. 



< Busycon, Adams, f. Gen. Moll. I., 1853, p. 151. 



< Busycon, Stimps., Am. Journ. Conch. I., 1864, p. 60. 



= FuJgur, Montf, Conch. Syst., II., 1810, p. 502, {carica and 

 jjerversus). 



< Fulgur, Gray, Proc. Zool. Soc, 1847, p. 135 ; Guide, 1867, 



p. 11. 

 Murex, sp. Linn., &c. 

 Pyrula, sp. Lam, Petit, &c. 



Etym. Fulgur, lightning ; in allusion to the coloration indi- 

 cating periods of increase simulating streaks of lightning. 



Animal rather small, retractile with its operculum within the 

 shell for about a third of a volution from the aperture. Radula 

 with the rachidian tooth 5 — 6 dentate ; lateral 5 — 6 dentate, 

 {F. carica; per versus fide Stimpson). 



Operculum with the nucleus apical. 



Shell with a simple very thin periostraca ; with little raised 

 revolving lines ; pyriform, with the whorls wound tightly round 

 the axis, leaving no umbilicus, angular behind, with the upper 



* = equal to ; < indicates a more extended group ; > a more re- 

 stricted one. 



