TRANSACTIONS OF WAGNER 

 1424 



TERTIARY FAUNA OF FLORIDA 



It appears both in Texas, Alabama, and New Jersey in the oldest Eocene, and 

 is associated with another allied species which will be described later. The 

 V . transversa Lea of the Claibornian is a short variety in which the posterior 

 ribs are particularly prominent. It nearly bridges the gap towards V. rotunda 

 Lea of the same horizon. The relations of rotunda to V. complexicosta Aldrich, 

 from the Wahtubbee Eocene of Alabama, appear close. V. carolinensis Con- 

 rad, from the Eocene of South Carolina, is imperfectly described from a doubt- 

 ful fragment and may be identical with V '. alticostata. It has not been figured. 

 On the other hand, the V. Blandingi Conrad, from the South Carolinian Eocene, 

 was described from a badly worn specimen obscurely figured and may be 

 identical with Lea's rotunda. V. siibrotunda Conrad is not unlikely to prove 

 the young of V. vigintinaria Conrad described at the same time from the Clai- 

 bornian horizon at Orangeburg, South Carolina, and itself an imperfectly 

 constituted species. 



Other imperfectly known species .are V. Brittoni Whitfield, from the older 

 Eocene of New Jersey, and V. bilineata Conrad, from South Carolina, the figure 

 of which recalls V. noridana Conrad. Cardita tetrica Conrad, of Wailes' " Re- 

 port on the Geology of Mississippi," is an absolutely nude name, as is his 

 Venericardia jacksonensis of the Eocene Checklist (No. 716). Both names 

 probably were intended to refer to the small Venericardia of the Jacksonian, 

 which closely resembles V . rotunda, but is higher, with more prominent and 

 elevated beaks, higher ribs, and very marked peripheral fluting. This is a 

 quite recognizable form for which Harris has adopted the name tetrica and 

 which he has also collected at Vince's Bluff, Arkansas. Still another form 

 related to rotunda, from Cleveland County, Arkansas, near Cross-Roads 

 Church, is V . prcecisa Dall, to be referred to later. None of these has the 

 terrace or elevated thread on each side of the rib which characterizes V. com- 

 plexicosta, though occasional specimens, especially of rotunda, show a tendency 

 to develop such lines, and they are found on the umbones of some of the Lisbon 

 specimens of V. planicosta var. Hornii. V. trapezium Tuomey, from the Eocene 

 of North Carolina, was insufficiently described half a century ago and has never 

 been figured. The whereabouts of the type is not known to me. 



Venericardia bulla n. sp. 

 PLATE 56, FIGURES 13, 14. 



Brown sandstone of the Midway horizon, east of the first small creek on 

 the road to Bastrop, Texas, from Old Garfield in the Austin quadrangle ; T. 

 W! Vaughan, United States Geological Survey. 



