MIOCENE PORPOISES — KELLOGG 103 



slope more backward than inward; diameters of alveolae diminish 

 more markedly toward hinder end of tooth series than anteriorly. 



Lophocetus calvertensis (Harlan) 



Delphinus calvertensis Harlan, Bull. Proc. Nat. Inst. Promotion Sci. Washington, 

 No. 2, pp. 195-196, 1842. 



Type specimen (UvSNM 16314): Incomplete skull, lacking both 

 zygomatic processes as well as supraorbital processes of frontals and 

 distal end of rostrum; left periotic; atlas, axis, third, fourth, fifth, 

 sixth, and seventh cervical and first and second dorsal vertebrae. Col- 

 lector, Francis Markoe, Jr., October-November 1841. 



Horizon and locality: Cove Point, Calvert County, Md. St. 

 Marys formation. 



Lophocetus pappus, new species 



Figure 1; Plates 1-11 

 Individual 1 



Type specimen (USNM 15985): Skull which lacks basicranium, 

 occipital condyles, supraoccipital, right squamosal and right zygo- 

 matic process; right and left mandibles; 75 detached teeth; left 

 periotic; right tympanic bulla; atlas; 3 cervicals; 4 dorsals; and por- 

 tions of 10 ribs. Collector, A. C. Murray. July 9, 1939. 



Horizon and locality: In compact sandy blue clay of Zone 11 

 (1 foot below base of Zone 12), about 8 feet above base of cliff, ap- 

 proximately nine-tenths of a mile north of mouth of Parker Creek, 

 Calvert County, Md. Calvert formation, upper Miocene. 



Individual 2 



Keferred specimen (USNM 20659) : Section of rostrum (225 mm. 

 in length), basal portion of left scapula, anterior dorsal vertebra 

 (incomplete), terminal caudal, and right periotic. Collectors, Rem- 

 ington Kellogg, C. Lewis Gazin, and Raymond M. Gilmore, Aug. 17, 

 1933. 



Horizon and locality: In sandy clay of Zone 14 (about 3 feet 

 above contact with Zone 13), approximately 956 yards north of old 

 pier at end of Governor's Run Road (see U. S. Geol. Surv. Prince 

 Frederick Quad.), Calvert County, Md. Calvert formation, upper 

 Miocene. 



SKULL 



Aside from differences in the conformation of the nasal bones, and 

 the amount of exposure of the frontals on the vertex, the skull of 

 Lophocetus pappus seems to differ from that of Lophocetus calvertensis 



