TRANSACTIONS OF WAGNER 



TERTIARY FAUNA OF FLORIDA 



'^Entodesma Philippi, Arch, fiir Naturg., i., p. 52, 1845; ibid., 1847, p. 66; Phil, type 

 E. chilense; Carpenter, Suppl. Rep. Brit. Assoc, for 1863, p. 638, 1864. 



^Philippina Dall, Moll. Porto Rico, Bull. U. S. Fish Com. for 1900, p. 498, 1901. Type 

 Lyonsia beana Orbigny. 



This group has had a varied synonymy as above noted. It is divisible into 

 the following subgenera : 



Subgenus Lyonsia s. s. Type L. norvegica Gmelin. 



Thin, elongated, with fine radial sculpture externally ; periostracum incon- 

 spicuous, usually with more or less adherent sand ; inoderately inequilateral. 

 Distribution world wide, but especially the colder seas. 



Subgenus Entodesma Philippi. Type E. chilense Philippi. 



Large, coarse, irregular, with the nestling habit, a very coarse periostracum, 

 hard, pearly shell, and a very large lithodesma. Distribution temperate and 

 tropical seas. 



Section Allogramma Dall, 1903. Type Lyonsia formosa Jeffreys. 

 Valves with radial and vertical undulations, gaping behind but not below ; 

 siphons very short, with a profusion of long, tentacular filaments and a slender, 

 cylindrical foot. 



Section Philippina Dall. Type Lyonsia beana Orb., 1845 (-|- brasilien- 

 sis Gould, 1850, + Orbignyi Fischer, 1857). 

 Shell small, thin, polished, very inequilateral, the anterior end short, attenu- 

 ated, gaping below, compressed behind, often with color painting. Distribution 

 in the warmer seas, commensal with sponges or compound Ascidians. 



Owing to the delicacy and usual situs of the shells of this genus it is rare 

 to find them in the fossil state. Of typical Lyonsia there are three species on 

 the Atlantic coast, L. floridana Conr., L. hyalina Conr., and L. arenosa Moller. 

 The latter is an Arctic species and is found in the Leda clays of the Pleistocene 

 in Maine, New Brunswick, and Quebec. It is the Osteodesma ceruginosa of 

 Mighels. Lyonsia (Allogramma) formosa has been dredged in the Gulf of 

 Campeche; Entodesma (Philippina) beana Orbigny extends from Cape Hat- 

 teras to the Brazilian coast, but neither is known in a fossil state. 



Lyonsia acuta n. sp. 

 Plate 57, Figure 24. 

 Pliocene marl of Shell Creek, Florida ; Burns. 

 Shell small, inequivalve, inequilateral, elongate, the beaks two-sevenths of 



