no TRANSACTIONS OF THE WAGNER FREE 



Busycon dumosum Conrad, Am. Journ. Conch, iii. p. 266, pi. 19, fig. 3, 1867. 



Fulgiir iiodulatus Gill, Am. Journ. Conch, iii. p. 147, 1S67. 



Busycon [Sycopsis) nodulatiim Conrad, Am. Journ. Conch, iii. p. 184. 



Busycon striatum Conrad, Am. Journ. Conch, ii. p. 69, pi. 3, fig. 8, 1866 (j-oung). 



It was very natural that Conrad should have described as distinct species 

 and even placed in two distinct subgenera extreme forms of this protean 

 species. Both in the Upper Eocene (Vicksburg) and the Lower Miocene 

 (Chipola River, near Bailey's Ferry and Alum Bluff, Chattahoochee River, as 

 well as the Tampa silex-beds) it riots in variation so luxuriant that one would 

 have good reason for naming half a dozen species, were these forms not abso- 

 lutely connected by the most trifling individual gradations. The spire may 

 be scalar or have the suture wound accurately on the keel. The keel may be 

 simple, tuberculous, or represented by a series of unconnected spines. The 

 external spirals may be numerous and fine, few and coarse, or, on the periphery, 

 obsolete; the space between the suture and the shoulder may be sloping, flat, 

 or excavated. The principal types are as follows: 



F. spiniger var. nodidattim (Conr.). Spire low, whorls keeled, suture wound 

 on or near the keel; shoulder flat, sloping; keel more or less nodulous, some- 

 times subspinous ; striation fine, often obsolete on the periphery ; pillar with 

 one groove ; throat lirate ; body with an internal ridge near the suture in 

 adults. Lower Miocene near the Chipola River, W. Florida. In examining 

 the types of this species in the Museum of the Academy of Natural Sciences 

 in Philadelphia, I found that on the same tablet with the genuine F. nodulatjim 

 is included one specimen of young F. coronatJim. 



F. spiniger v2iX. spiniger {Conr). Spire more elevated, subcarinate ; shoulder 

 excavated, appressed at or near the keel ; keel at first obscure, with many 

 pointed nodules, later with only isolated spinous nodules. 



Upper Eocene at \'^icksburg, Miss. Lower Miocene near the Chipola 

 River, West Florida. 



This form has the spirals as strong as or stronger than var. nodtilatum where 

 present, but the periphery is often bare of spirals altogether, and there is fre- 

 quently a narrow, smooth band in front of the suture, occasionally a little 

 excavated, which is the herald of the sutural channel in subsequent forms. 

 As the var. spiniger increases in size the spines become more imbricate or like 

 those of F. pervers7mi, with the anterior slope much the shorter. In small 

 and average specimens the two slopes are nearly alike measured in the direc- 

 tion of the whorl, or spirally. Large ones measure 80 mm. long. 



F. spiniger var. Burnsii Dall. Spire moderate ; keel often nodulous or 

 even faintly undulate, instead of spiny ; shoulder flatfish, with a thick band 

 or swollen cord at the suture, which is deep, though not quite channelled ; 

 spiral sculpture sparse, but very coarse ; periphery smooth ; internal lirse 

 prominent and continuous, rather sparse ; infra-sutural callus strong and sharp. 

 Max. Ion. observed, about 65 mm. The spire varies from depressed to 



