92 COMMON AMERICAN SHREW MOLE. 



Dr. Richardson described a specimen which was obtained on the Co- 

 lumbia river, (P. B. A., p. 9,) which contained forty-four teeth, very 

 differently arranged. This animal he referred to our common Shrew 

 Mole, supposing that the difference in the dentition, as observed by diffe- 

 rent authors, was owing to their having examined and described speci- 

 mens of different ages. 



In 1840, Professor EMiwoNg (Report on the Quadrupeds of Massachusetts,) 

 characterizes the genus as having 44 teeth. In 1842, Dr. Dekay, (Nat. 

 History of the State of New York, p. 15,) has very erroneously given as a 

 character, its having from 34 to 46 teeth, and states that he had once seen 

 the skull of one of this species containing 44 teeth. 



In an article in the Boston Journal, (vol. iv., No. i., p. 26, 1842.) We 

 endeavoured to explain and correct the contradictory views of former 

 authors, and we feel confident we have it in our power to account for the 

 skull seen by Dr. Dekay, containing forty-four teeth. 



The specimens examined by Baron Cuvier, Desmarbst, and Dr. Harlan, 

 each containing but 30 teeth, were evidently young animals, with their 

 dentition incomplete. One half of the specimens now lying before us, 

 present the same deficiency in the number of terth ; they also exhibit the 

 edentate spaces between the incisors and grinders remarked by those au- 

 thors. We have, in deciding this point, compared more than fifty speci- 

 mens together. Those on the other hand that were examined by F. Cu- 

 vier, and Dr. Godman, and the skeleton of Dr. Harlan's Scalops Pennsyl- 

 vanica, containing 36 teeth, were adults of the same species. Dr. Richard- 

 son's specimen was a new species, (Scalops Townsendii,) having 44 teeth, 

 (see Journ. Acad. Nat. Sc, Philadelphia, vol. viii., p. 58.) With re- 

 gard to the skull seen by Dr. Dekay, we have no doubt of its having be- 

 longed to Scalops Brewerii, (see Bost. Journ. Nat. Hist., vol. iv., p. 32,) 

 which has 44 teeth, and is not uncommon in the State of New York, as 

 we obtained four specimens from our friend, the late Dr. Wright, who 

 procured them in the vicinity of Troy. 



