1886.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 97 



DESCRIPTION OF A NEW GENUS AND SPECIES OF MOLE, DYMEC- 

 ODON PILIROSTRIS, FROM JAPAN. 



By FREDERICK W. TRITE. 



Seveu years ago, at the request of Prof. E. S. Morse, the authorities 

 of the Boston Society of Natural History sent to the National Museum 

 two specimens of mammals in alcohol, from Yenosima, at the mouth of 

 the Bay of Yeddo, Japan. The bottle in which they were contained 

 having been misplaced, they have remained unidentified until the pres- 

 ent time. One of the specimens is a common house-rat, 3Ius decumamis ; 

 the other is an insectivore belonging to a genus hitherto undescribed. 



The latter specimen closely resembles Urotrichus talpoides in general 

 appearance, but differs in dentition as well as in proportions.- - 



Diagnosis. 



Dymecodon,* new genus. 



General appearance of Urotrichus. Dentition as follows : 



I. I 0.1 PM.| M.|x2=38. . 



Anterior incisors broad, spatulate. 



DYMECODON PILIROSTRIS, UeW SpCCieS. 



General appearance of U. talpoides : Tail vertebrae almost exactly 

 one-half the length of the head and body ; with the hairs, two-thirds the 

 same length. Soles and palms entirely covered with scales ; snout with 

 rather long, fine, dark bairs. 



General description. 



The chief differences separating this animal from Urotrichus and Xeil- 

 rotrichus lie in the form and number of the teeth. The first superior 

 incisor is low and broad, and resembles the teeth of Phoccvna in appear- 

 ance. It is the broadest tooth anterior to the true molars. The second 

 incisor is nearly as large as the first, and resembles it in shape. The 

 third incisor is very small — about one-fourth the size of the first. The 

 crown is simple and rounded. The canine resembles the third incisor 

 in size and shape. The first premolar is intermediate in size between 

 the first and second incisors, and is conical and pointed. The second 

 premolar is smaller than the second incisor, and rounded. The third 

 premolar and the true molars are as in Urotrichus. 



*Teetli of two lengths — from 5vo, two ; /iffxoS, length; oSovi. tooth. Refers to 

 the alternation of large and amall teeth in the lower jaw. 



Proc. N. M. 86 7 l§epteniR>er 2, 1886. 



