TERTIARY MOLLUSCA. L1V 



Myrtsea(?) asphaltica, new species. 

 (Plate 14, Figures 7 a, b, 8, 9 a-c.) 



The following is a description of this species: 



Shell large, robust, transversely elliptical, lucinoid; anterior and ventral 

 margins rounded, posterior margin truncated; beaks full, situated a little in 

 front of the middle; surface sculpture of rough, crowded, concentric growth- 

 lines and, on the umbones, equidistant, concentric ridges, becoming obsolete 

 distally; dorsal areas obsolete; inner margins entire; anterior adductor scar 

 lucinoid but rather short; lunule broadly lanceolate; escutcheon linear or nar- 

 rowly lanceolate, depressed, bordered by a sharply angular keel; hinge with 

 1 right and 2 left cardinal teeth, 1 right and 2 left anterior laterals, and the 

 same number of posterior laterals; left laterals feeble; ligament external but 

 deeply depressed, preserved in the types. 



Alt. of a medium-sized specimen, 40 mm.; length, 49 mm.; diam., 25 mm. 

 A larger specimen measures 57 mm. in altitude and 39 mm. in diameter. 



This exceedingly interesting species, undoubtedly a member of the 

 family Lucinidse, is closely related to Myrtsea, but is very much larger 

 than any hitherto described American species of that genus, and has 

 weaker sculpture than is customary. It is separated at once from 

 Lucina by its dentition and escutcheon; from Loripes by the escutcheon, 

 external ligament, and dentition; and from the greater number of 

 Phacoides by the absence of dorsal areas. 



Locality. — Angela Elmira asphalt mine, near Bejucal, Cuba, stations 

 3652, 5312, Wiebusch. 



Geologic horizon. — Oligocene? 



Type.—U. S. Nat. Mus. No. 167186. 



Phacoides (Miltha) aff. Phacoides hillsboroensis (Heilprin). 

 (Plate 15, Figures 3 o, 6.) 



This species, which is known only from casts of the interior, resembles 

 rather closely Miltha hillsboroensis, from which it differs in its more 

 depressed posterior dorsal areas. 



Alt., 62 mm.; lat., 62 mm.; diam., 26 mm. 



Localities. — Near Santiago, Cuba, stations 3192 and 5255, Willcox, 

 Black. 



Geologic horizon. — Oligocene. 



Figured specimen. — U. S. Nat. Mus. No. 167189. 



Phacoides (Here) species. 

 (Plate 15, Figure 2.) 



The following is a partial description of this species : 



Right valve resembling P. wacissanus Dall but with straighter dorsal margin 

 and more deeply impressed sulcus, which extends with undiminished depth to 

 the beak; left valve with shallower sulcus. 



The specimens probably represent an undescribed species, but are 

 too fragmentary to furnish a complete diagnosis. 

 Locality. — Crocus Bay, Anguilla, stations 6965, 6894, Vaughan. 

 Geologic horizon. — Oligocene. 

 Figured specimen. — U. S. Nat. Mus. No. 167190. 



