66 REPORT OF NEW JERSEY STATE MUSEUM. 



Genus Synaptomys Baird. 

 Lemming Mice. 



Synaptomys cooperi Baird. 



Cooper's Lemming Mouse. 



Plate 2'i, Fig. 2. 



Length 4.80 inches. Upper front teeth grooved, tail very short 

 (about three-quarters of an inch). Color sepia brown, mixed 

 with many black hairs, some individuals with a few buff or red- 

 brown hairs, others grayer. Below plumbeous, with whitish tips 

 to the fur, ears very short, overtopped by the hair ; mammae six. 



This little mouse is externally the counterpart of the Meadow 

 mouse, with which it associates, but can be distinguished by the 

 grooved incisors and the somewhat shorter tail. It was originally 

 described by Prof. Baird in 1857, and until 1888 no other speci- 

 men was obtained east of the Alleghanies, although a few had 

 been found in the Mississippi Valley. In that year and the fol- 

 lowing, five skulls were discovered in owl pellets and in the 

 stomach of a hawk and an owl. These were from Virginia, 

 Maryland and New York. In August, 1892, Dr. Merriam suc- 

 ceeded in trapping the mice themselves on Roan Mountain, North 

 Carolina, and in a paper reviewing the history of this interesting- 

 little animal, he advised those interested in the capture of rare 

 mammals to look out for it in Pennsylvania and New Jersey. 

 Before this paper appeared, however, a specimen was secured by 

 Mr. S. N. Rhoads in a bog near May's Landing, N. J., December 

 2, 1892. Two others were later secured in the same spot and four 

 more at Tuckahoe and Port Norris. These, so far as I am aware, 

 constitute all the New Jersey specimens except Baird's original 

 example, which is thought to have come from Hoboken, although 

 its exact place of capture is not known. Mr. William Cooper, 

 from whom he received it, lived in Hoboken and hence the infer- 

 ence. In other parts of the country many additional examples 

 have been procured. Mr. Rhoads was under the impression that 



