1 7*^ 



1869.] ^ "^ [Cope. 



bore these teeth. They are more compressed than in the Beaver, and 

 deeper than in the Vischaca ; they are not so narrowed anteriorly as in 

 the agutis. The solidity is only approached by the Castorides o h i e n s i s, 

 and to some degree Amblyrhiza i n u n d a t a, of the same period. 



Castor fiber., Linn. C. Canadensis, Kulil. 



Portion of mandible with three molars, not distinguishable from recent 

 specimens. 



Neotoma magister, Baird. Mammals of North America, p. , tab. 



Said to be larger, and otherwise different from the following. Found 

 in the Bone Caves near Carlisle, in the great Appalachian Valley, in 

 Pennsylvania. 



Neotoma ? florid ANUM, Say. et. Ord. 



A superior molar, incisors, and other portions. The first is not larger 

 than in recent animals, and does not conform in peculiarities to those 

 ascribed by Baird to his N. magister from the Pennsylvania Bone 

 Caves. The latter is, however, described from mandibular pieces. 



The recent Neotoma of this species is exceedingly common in all of the 

 caves which I examined. Their marks can be found from near the 

 mouths to the most remote recesses. They build, in dry places in the 

 more distant chambers, nests of complete and durable construction. In 

 such a chamber in the Hoge's Cave, Montgomery County, Va., I found 

 a number of these nests near together and fastened by interwoven sticks 

 and corn-husks in some mass, to the points and crevices of the rocks. 

 The tipper surface of the x^iie, in which the nest was made, was composed 

 apparently of chewed linden bark, forming a soft, tough, and nearly 

 white material. This surface was always oblique, and enclosed a round 

 cavity, large enough to hold one's two fists', which was entered by a mouth 

 a little more contracted than the whole diameter. Numerous fresh seeds 

 of the Celtis pumila lay about them. They are sweet, and the small 

 tree which produces them is abundant where the traces of the cave were 

 foimcl. Seeds undistinguishable from these are abundant in the limestone 

 breccia with the remains of Neotoma, and testify to the identity of habit 

 of this species in the days of Tapirs, Peccaries and Sloths. 



Arctomys MOKAx, Omsl. The Ground Hog. One nearly perfect ramus 

 mandibuli with all teeth but the last molar, not distinguishable from re- 

 cent examples. 



Found also at Galena. (See Leidy, Trans. Amer. Phil. Soc, XL, p. 

 100.) 



Arvicoi.a, Sp. Noted by Leidy, 1. c, from Galena, 111. 

 Geomts btjrsarius. Leidy, 1. c. , p. 100. 



Found at Galena by Dr. E. D. Kittoe with numerous other species 

 enumerated by Leconte and Leidy. 

 Hesperomys '? LEUcoPUs, Raf. 

 Molar teeth undistinguishable from those of this common mouse. 



