TRANSACTIONS OF WAGNER 

 S9 2 



TERTIARY FAUNA OF FLORIDA 



This shell is remarkably like a small Leda from the Claiborne sands 

 which I have without a name, but is more rounded behind. More material is 

 needed to establish its exact relations. Another valve was found at Plum 

 Point which may be distinct, or possibly a variety of this species, from which 

 it differs by its thinner shell and by having fine concentric sculpture on and 

 near the beaks and on the anterior dorsal slope. 



Leda phalacra n. s. ? 



Miocene of Plum Point, Maryland ; Burns. 



This shell, also represented by a single valve, is less arcuate and more 

 compressed than L. ainydra ; the middle third of the convexity of the shell 

 has a few conspicuous concentric waves which do not reach the base and end 

 abruptly before and behind ; the beaks are covered with concentric sculpture, 

 which also appears on the anterior dorsal slope ; there is a well-marked 

 narrow, impressed lunule and escutcheon, but the hinge, though feeble, resem- 

 bles that of L. ainydra. Lon. 5.5, alt. 2.7 mm. 



These little Yoldiform Ledas would be easily mistaken for Yoldias; and, 

 in fact, many have been so referred by authors, but sufficient study will 

 enable almost any of them to be properly referred. While the distinctions 

 are chiefly anatomical, the solidity of the shell, the presence of a rostral ray, 

 a lunule, and concentric or radial sculpture are all characteristic of Leda and 

 not of Yoldia, and some of these characters are almost always present, and 

 taken with the general habit of the shells are sufficient to distinguish them. 



I may add that I have fragments of a beautiful Adrana from the Pliocene 

 of Limon, Costa Rica, but prefer to await better specimens before attempting 

 to name it. 



Leda acuta Conrad. 



J\'u/ i//ir atli/ii Conrad, Am. Mar. Conch., p. 32, pi. vi., li<j. I, 1831 ; not of Sby., Trans. 



(icol. Sor. I. ond., 2cl Ser., v., pi. 39. fijj. 5, 1837. 

 Leda cimcala Sby., I'. /,. S., 1832, p. 198. 

 I.fi/ii /nHtii/i'i'/is/.i Orb., Moll. Cuba, ii., p. 262, pi. xxvi., rigs. 27-29, 1846; Dull, Hull. 



Mus. Comp. /ool., ix., p. 124, 1881. 

 Leda iincti ('.Id., 1'roc. Host. Soc. Nat. Hist., viii., p. 282, 1862; Verrill, Trans. Conn. 



Acacl., v., p. 572, 1882 ; not vi., p. 260, 1884. 

 Lfda inornala A. Ads., Jidf Hanley, from type. 

 Leda acnta (Conrad) Dall, Hull. Mus. Comp. /ool., \ii., p. 251, 1886; xviii., p. 438, 



1889. 



