TRANSACTIONS OF WAGNER 

 1384 



TERTIARY FAUNA OF FLORIDA 







lamellation, distinctly impressed dorsal areas, and larger average size. Alt. 

 7.5, Ion. 7.5, diam. 6.5 mm. 



There is some variation due to age and some to variability of the individual, 

 but on the whole the species is quite constant in all its features except the 

 strength of the radial sculpture. Differences due to wear of the concentric 

 lamellation are, of course, common and to be allowed for. 



The shell enumerated in Mr. Searles Wood's Catalogue of Crag Fossils in 

 the " Annals" for 1840, under the name of Lucina crenulata, but not described 

 until later, belongs to the same group as the present species, but appears to me 

 specifically distinct from it after a comparison of specimens. 



Phacoides ( Parvthicina ) prunus n. sp. 

 PLATE 52, FIGURE 8. 



Miocene of Plum Point (abundant) and St. Mary's River, Maryland, and 

 the James River, Virginia ; Burns. 



Shell resembling P. crenulatns but flatter, more inequilateral, with thicker 

 and more regular concentric ribs, no radial sculpture, the inner margins more 

 finely crenulate or even smooth, lunule shorter and wider, and the posterior 

 dorsal area narrower and more vertical than in P. crenulatns. Alt. 6.5, Ion. 7.0, 

 diam. 4.0 mm. 



The beaks are much more prominent and more recurved over the small 

 globular lunule, the ribs are wider than their interspaces, and the radial struct- 

 ure is seen only when the shell is decorticated. 



Phacoides (Parvilucina) multilineatus Tuomey and Holmes. 

 Lucina multilineata T. and H.. Pleioc. Fos. S. Car., p. 61, pi. xviii.. figs. 16, 17, 1857; 



Emmons, Geol. Rep. N. Car., p. 291, 1858; Holmes, Post-Pi. Fos. S. Car., p. 30, pi. 



vi., fig. 6, 1860. 

 TPhacoides (Parvilucina) crenella Dall, Synopsis Lucinacea, pp. 810. 825, pi. xxxix., fig. 2, 



1901. 



Pliocene of North Carolina at Croatan ; Tilly's Lake, Waccamaw district, 

 South Carolina ; of the Caloosahatchie beds in Florida on the Caloosahatchie, 

 Myakka, and Shell Creek ; Pleistocene of Simmons Bluff, South Carolina, and 

 North Creek, near Osprey, Florida. 



This is a fine, plump little shell, in which the concentric sculpture is so 

 reduced that it forms a feeble cancellation with the usually coarser but some- 

 what variable radial threads. The lunule is short and quite deeply impressed, 

 and the marginal crenulations coarser than in P. crenulatus. The identity of 

 the recent species with it is probable but not certain. 



