MARINE MOLLUSCA OF THE UNITED STATES. 23 



Genus SYCOTYPUS, Browne. 

 NaJ. Hist., Jamaica, 406. 1756. 

 Busycon, Bolteu, Morcli, Yoldi, Cat. 104. 1852. 

 Fulgur, Montfort, Couch. Syst., ii. 502. 1810. 

 Pyrula, Lam. (part.) Prodr. 1799. 



Shell pyriform, thin, last whorl large, nodulous or spinose ; spire 

 very short; aperture large, sub triangular ; canal open, elongated, 

 entire at theYorepart; inner lip concave, with a single fold ante- 

 riorly ; outer lip internally striated. 



The species are mostly American and are principally southern. 

 Recent authorities have separated the shells with canaliculated 

 sutures under the generic name Sycotypus, leaving the other spe- 

 cies to constitute the genus Fulgur •= Busycon. As I fail to ap- 

 preciate the necessity for this division I have reunited them under 

 the name of Sycotypus. 



* Canaliculate around the suture. 



1. S. canaliculatus, Linnreus. Figs. 26, 27. 



{Murex.) Syst. Nat., edit. xii. 1222. 

 Pyrula canaliculata, Brag., Ency. Meth. Vers. iii. 866, t. 436, f. 3. 

 Pyrula spirata, Kiener, Iconog., t. 10, f. 1. 

 Sycotypus canaliculatus, Gill., Am. Joum. Conch, iii. 149. 1867. 



Shell large, pear-shaped, covered with revolving lines, and a 

 hispid epidermis ; lower whorl tumid, ending in a long canal ; a 

 nodular keel crowns the flattened summit of each whorl, and there 

 is a deep and broad channel at the suture. 



Fig. 27 represents a string of egg cases. 



Cape Cod, Massachusetts, to Georgia. 



2. S. pyrum, Dillwyn. Fig. 28. 



{Bulla.) Desc. Cat., i. 485. 1817. 

 Pyrula spirata, Lamarck, Anim. s. Vert., vii. 142. 1822. 

 Fulgur pyruloides, Say, Journ. Philad. Acad., ii. 237. 

 Busycon plagosum, Conrad, Prov. Acad. Nat. Sciences, Philad. 583. 1862. 



Shell with spiral strire alternately larger; whorls white, trans- 

 versely lineated with ferruginous lines, interrupted or obsolete on 

 the middle; above flattened, unarmed; spire short, suture pro- 

 foundly canaliculate. 



Southern Coast, Gulf of Mexico. 



** Suture not canaliculate. 



3. S. carious, Gmelin. Figs. 29, 30, 31 (reversed variety). 



(Murex.) Syst. Nat., 3545. 1788. 



