TRANSACTIONS OF WAGNER 



742 



TERTIARY FAUNA OF FLORIDA 



submargins small, narrow, with fine, beaded radial threads, which in the left 

 valve also extend over the ears ; hinge-line short, the cardinal crura developed, 

 sharply cross-striated; auricular crura present; interior of the disk fluted in 

 harmony with the external ribs. Alt. 30, lat. 25, semidiam. 5 mm. 



A single left valve of this elegant species was obtained. From the young 

 of P. Madisonius, which sometimes approach it, it is easily distinguished by its 

 more oval and inflated form, nearly smooth interspaces, and compressed ribs. 



Pecten (Chlamys) Harrisii n. s. 

 PLATE 34, FIGURE 24. 



Pliocene marls of the Caloosahatchie River; Dall and Willcox. 



Shell strong, rounded, with seventeen coarse, rounded ribs with narrower 

 interspaces, overrun by close-set, prominent, slightly wavy, strong concentric 

 lamellation ; near the basal margin the ribs and interspaces are marked with 

 a few sharp radial stria? ; submargins and ears with smaller radial threads 

 similarly lamellose ; notch narrow, deep ; ctenolium present, short ; interior 

 of the disk strongly fluted, lirate ; cardinal crura strong, auricular crura 

 feeble. Alt. and lat. 31, semidiam. 7 mm. 



A single adult right valve and numerous immature ones were obtained. 



The valve figured is a little irregular. The young shells are proportion- 

 ately flatter and with wider ears. They have, as often observed in the young 

 of P. exasperatus, in some cases three or four of the ribs more prominent 

 than the rest, and the lamellation worn off from the tops of the ribs or in- 

 complete there. The species is named in honor of Professor G. D. Harris, of 

 Cornell University, whose work on the Eocene fossils of the Southern States 

 is well known. 



Pecten (Chlamys) exasperatus Sowerby. 

 '? Pecten nniscosus Gray, Wood's Ind. Test. Suppl., pi. 2, fig. 2, 1828 ; Sby., Thcsaur. 



Conch., Pecten, p. 66, pi. xix., fig. 225, 1843 ; Reeve, Conch. Icon., viii., pi. 16, fig. 



60, 1853. " South Seas." 

 Pecten exasperatus Sby., Thesa'ur. Conch, i., p. 54, pi. 18, figs. 183, 184, 186, 1843 ; 



Reeve, Conch. Icon., viii., pi. 2, figs. 7, &a-l>, 1852; Dall, Bull. U. S. Nat. Mus., 



No. 37, p. 34, 1889. "Mediterranean." 

 Pecten triradiatus Reeve, Conch. Icon., viii., pi. 28, fig. 120, 1853 ; not of Miiller, Zool. 



Dan., ii., p. 25, 1788. 



Pecten cretatus Reeve, op. cit., pi. 29, figs, \2ga-b, 1853. 

 Pecten fuscopurpurcus Conn, Journ. Acad. Nat. Sci. Phila., N. S., i., pp. 209, 280, pi. 39, 



fig. 10, 1849. Tampa, Fla. 



