NO. 1101. PBOCEEDINGS OF THE NATIONAL MUSEUM. 79 



Average dimensions (21 alcoholic specimens, males and females). — 

 Total length, 170 mm.; tail vertebra, 71.8 mm.; hind foot and claw, 

 27.1 mm. 



Average dimensions of skulls. 



mm. 



Greatest length (9) 35. 2 



Basilar length (Hensel) (10) 27.6 



Greatest zygomatic breadth (7) 10. 2 



Palate length (10) 13.5 



Length of npper tooth row (base of crowns) (11) 1.5. 2 



Breadth of jiostorbital constriction (11) 7. 1 



Length of mandible, from inner base of incisors to end of angular process (11). 21.8 



Type locality. — Pennsylvania. 



Geographical distribution. — Rupert House and Moose Factory (Hud- 

 sou Bay), Quebec, Ontario, and Manitoba on the north, southward to 

 Minnesota on the west, to Virginia on the zVtlantic Coast, and in the 

 Alleghany Mountains to the boundary of South Carolina. 



DESCRIPTION. 



Form robust. Legs short. Snout broad and only moderately elon- 

 gated, extended about 7 mm. beyond the anterior upper incisors in 

 adults. Nostrils circular, opening forward on the surface of a naked 

 disk, which is surrounded by a fringe of 22 naked 

 lanceolate processes about 4.5 mm. long. These 

 processes are symmetrically arranged, 11 on each 

 side of the median line. Those forming the inner 

 pairs above and below the nostrils are smaller 

 than the others and have their origin on the an- 

 terior face of the disk rather than on its margin. 

 The upper surface of the snout is naked as far 

 backward as the point reached by the extremity 

 of the nasal processes when laid back upon it. 



Corner of the mouth anterior to the line of the eyes. Upper lip 

 grooved in the median line below the nasal disk. Inside its margin a 



NASAL DISK OP CONDTLDRA. 



(Twice natural size.) 



28. 



SNODT OF CONDYLDRA CEISTATA. 

 Fig. 28, Upper surface. Fig. 29, Lower surface. Fig. 30, Side view. 



thin ridge extends from the median line nearly to the corner of the 

 mouth. Lower jaw naked at the extremity. 



