TRANSACTIONS OF WAGNER 

 1 I 14 



TERTIARY FAUNA OF FLORIDA 



sinuous specimens of which Gregorio (Mon. Claib., 215, 1890) has proposed 

 the varietal name of mittens. His magnified figure of the posterior sculpture 

 is quite inadequate. P. gambrina Gabb, from the Texas Oligocene, is the 

 young of P. diversa, as Gabb suspected. P. Neivberryana Gabb, 1881, from 

 the Oligocene sandstones of Gatun, on the Panama Canal, has the appearance 

 of a cast of P. diversa, but is really unrecognizable. 



There is a small species in the Bowden marl of Jamaica which much re- 

 sembles the recent P. peramabilis Dall, but on the Pacific coast the Tertiary 

 has not yet furnished any species, though there is a recent species, Cardinin 

 centifiloswn Cpr., 1863 (+ C Richardsoni Whiteaves, 1878), as well as the 

 lovely P. [Lophocardium) Anneltcc DsW, 1889, and P. (L.) C umin gi Sowtrhy, 

 1833- 



Protocardia jamaicensis n. sp. 

 Plate 48, Figure 3. 



Oligocene of the Bowden marl, Jamaica ; Henderson and Simpson. 



Shell small, plump, subquadrate, with rather high SLibcentral umbones; 

 anterior end evenly rounded, posterior very slightly rounded truncate ; surface 

 with very numerous radiating threads crossed by concentric lines evenly dis- 

 posed, which at the intersections reveal themselves by rendering the radii 

 beaded; this sculpture covers a little less than the anterior half of the disk, 

 behind which the radials are narrower and not beaded, separated by still 

 narrower channels ; in the channel separating the anterior from the posterior 

 type of sculpture rises a low crest like a string of small beads, behind which 

 in each second or third channel rises a row of small, stout, very caducous spines, 

 those on the posterior area smaller and shorter than those on the disk ; inter- 

 nally the margin is minutely serrate ; the hinge is normal. Lon. 6.2, alt. 6.0, 

 diam. 4.5 mm. 



This species is nearest Protocardia peramabilis Dall, a recent deep-water 

 species of the Antilles, but differs by its smaller size, more delicate sculpture, 

 and less numerous rows of spines. It is also differentiated from the other 

 living Antillean species, P. tincta Dall, by its sculpture and much smaller size. 



Superfamily LEPTONACEA. 



The Leptonacca form a very interesting and puzzling group. Their char- 

 acters combine features characteristic in other Teleodonts of immaturity, with 

 such as are more probably due to environmental modifications. Without being 

 in themselves prototypes, they exhibit features which we may readily suppose 

 might have been characteristic of prototypic Teleodonts. Groups which are 



