424 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 



A cast of a skull (from an unknown locality) now before me lias a length 

 of over twelve inches, considerably exceeding in size the Clyde skull 

 described and figured by Dr. Wyman. The species being known only 

 from a few cranial and dental remains, it is impossible to say much respect- 

 ing its general form or probable habits. It may have been aquatic, like 

 the Heaver; but of this there is no evidence. The form of the occipital 

 condyles and the surfaces for the attachment of the cranial muscles show that 

 it probably (littered greatly in haoits from the Beaver. Mr. J. W. Foster 

 described (anonymously) a radius found with the two mandibular rami 

 discovered at Nashport, Ohio, which he presumed to belong to the same 

 animal. This bone he describes as being ten inches in length, and as 

 measuring two inches across the head and one and a half across the distal 

 extremity.* In a later notice of the same specimens, Mr. Foster makes no 

 mention of this bone, and no other naturalist appears to have given any 

 further account of it. Mr. Foster regarded it as "an animal closely allied to 

 the Beaver, hut far surpassing him in magnitude". Dr. Wyman not only does 

 not refer to it as a Beaver, but dwells especially upon the important differ- 

 ences that separate it from that animal. 



The remains of Castoroides ohioensis thus far reported consist of the two 

 right rami of the lower jaw and an upper incisor from Nashport, Licking 

 County, Ohio (from which the animal was originally made known), first 

 described by Foster; the skull and a right ramus of the lower jaw from 

 Clyde, Wayne County, New York, described (and the skull figured) by 

 Wyman; the ramus of a lower jaw from Memphis, Tennessee, also described 

 and figured by Wyman ; ''two molars, an upper incisor, and two petrous 

 hones '', from near Shawneetown, Illinois, and fragments of teeth from the 

 Ashley River, South Carolina, described by Leidy. A skull from near 

 Charleston, Coles County, Illinois, is also mentioned by Leidy. Hall and 

 Wyman both refer to the discovery of its remains near Natchez, Mississippi, 

 and in Louisiana; but I have met with no description of specimens from these 

 localities. Winchell mentions the discovery of its remains in Michigan, of 

 which uodescription has yet appeared. In the Museum of Comparative Zoology, 

 Cambridge, Massachusetts, are portions of several lower incisors and parts of 

 several molar teeth, from Dallas, Dallas County, Texas, collected by Mr. J. Boll, 

 from ''alluvial" deposits on the Trinity River, associated with remains of an 



* Amer. Joura. Sci. aud Arts, 1st ser., vol. xxxi, 1837, p. 80. 



