TERTIARY MOLLUSCA. 135 



This species closely resembles the figure of P. cercadica Maury from 

 Cercado de Mao, Santo Domingo, but seems to be a little less spreading 

 and to have differently shaped ears. In the description of P. cercadica, 

 a left valve, no mention is made of any grouping of the growth-lines on 

 the disk. 



This species is named in honor of Miss Julia Gardner, whose mono- 

 graphs (unfortunately delayed in publication) on the Miocene Mol- 

 lusca of Virginia and North Carolina and of the Alum Bluff formation 

 constitute an important contribution to American paleontology. 



Locality. SantiagOvCuba, station 3440, Vaughan. 



Geologic horizon. Uifi^ocene. 



Type.U. S. Nat. Mus. No. 167113 (right valve). 



Figured specimen. U. S. Nat. Mus. No. 167114 (left valve). 



Pecten crocus, new species. 



(Plate 9, Figures 2 a, 6; Plate 11, Figure 9.) 



The following is a description of this species : 



Shell equivalye, inequilateral, moderately convex; about 22 round ribs, 

 separated by slightly narrower interspaces; surface of the ribs with curved 

 imbricating spines, convex towards the umbones, and with very faint radiating 

 striae; interspaces with sculpture of fine, close-set, concentric striae; near 

 the ventral margin a small thread ^ appears in each interspace ; submargins 

 depressed, ornamented with small radial threads and fine concentric striae; 

 ears moderately large, subequal, with radial, nodose riblets. 



Alt., 39 mm.; lat., 36 mm.; diam., 14 mm. 



Locality. Roadside, descent to Crocus Bay, Anguilla, station 6893, 

 also 6894 and 6965, Vaughan. 

 Geologic horizon. Oligocene. 

 Type.U. S. Nat. Mus. No. 167079. 



Pecten (Lyropecten) pittieri Dall. 



(Plate 13, Figure 5.) 

 Pecten (Lyropecten) pittieri Dall, Smithsonian Misc. Coll., vol. 59, No. 2, p. 10, 1912. 



The following is the original description of this species: 



"Shell large, nearly equivalve, suborbicular, coarsely sculptured; left valve 

 moderately convex, with ten strong rounded ribs, obsolete distally, with shal- 

 low rounded interspaces at first narrower, afterwards wider than the ribs; 

 submargins wide, subequal, radially sculptured with coarse, somewhat irregu- 

 lar threads, about ten in number, which when perfect have a fine, concentric, 

 imbricate sculpture; similar radial sculpture covers both valves, the threads 

 coarser and more regular on the right valve; of the major ribs on the left valve, 

 five alternating ones bear on their proximal halves six to ten prominent, thin 

 evenly spaced, vaulted scales, resembling those of P. imbricatus Gmelin; 

 similar scales are wanting in the right valve ; ears subequal, with about half a 

 dozen radial threads and dense, concentric sculpture; margin of the valve 

 wavy, not sulcate; interior with ten deeply channelled, wide sulci correspond- 

 ing to the external ribs, the angles of the interspaces emphasized near the 

 valve margin; hinge with a deep sub triangular pit for the resilium, a strong 



