FREE INSTITUTE OF SCIENCE 



729 



TERTIARY FAUNA OK FLORIDA 



the Antilles and the north coast of South America ; living in the Gulf of 

 Mexico and the Antilles, and probably also (as /'. subnodosits) on the Pacific 

 shores of middle America. (Cf. remarks under Lyropecten and P. sitbnodosus 

 Sby., pp. 701, 710.) 



This species is the type of the section Nodipcctcn. It varies in the 

 number of ribs (seven to ten) and extremely in its amount of nodulation. 

 Some specimens have merely turgid undulations of the ribs, as in the form 

 first described of the Pacific siibnodosiis. Others bear subglobular bulLne on 

 the ribs at short intervals. Others begin without nodes and after half their 

 growth is accomplished suddenly become nodulous. P. siibnodosits varies in 

 the same way. The deeper the water, apparently, in which the individual 

 lives, the thinner and more nodose the shell. Mr. Willcox found some 

 remarkably fine specimens in the marls of the Caloosahatchie. 



Pecten (Nodipecten ?) peedeensis Tuomey and Holmes. 

 l't-cti-n pfi-Jfi-nsis T. and H., I'leioc. Fos. S. Car., p. 30, pi. 12, figs. 1-5, 1855. 



Miocene of the Peedee River, Darlington District, South Carolina, and 

 of Virginia. 



This fine species frequently has the younger part of the shell nodose and 

 the distal portions of the ribs wider, feebler, and less nodose. It has eight 

 or nine ribs and conspicuous concentric lainellation. It seems nearly inter- 

 mediate between the Lyropecten and Nodipcctcn types, and may belong to the 

 section Macrochlamis Sacco (Bull. Mus. Zool. Torino, xii., No. 298, p. 101, 

 June, 1897, type P. latissimns Brocchi). 



Pecten (Nodipecten) condylomatus n. s. 

 PLATE 34, FIGURES 14, 15. 



Oligocenc of White Beach, Osprcy, Florida, and of the Chipola River at 

 Bailey's Ferry, Florida, Burns and Dall ; lower bed at Hawkinsville, Georgia, 

 Burns. 



Shell small for the group, subequilatcral, slightly inequivalve, the right 

 valve more convex with nine to thirteen strong, undulated, rounded, more 

 or less nodulous, finely radially striated ribs, the undulations affecting the 

 whole of the disk, sudden and very pronounced, giving a side view of the 

 valve somewhat the aspect of a clenched fist ; interspaces narrower radially, 

 finely threaded, the whole valve with fine concentric lamellation somewhat 

 prickly or limose at the intersections ; submargins rather wide, radially finely 



