418 Notes on some Small Rodents found in North America. 



forget the exquisite pleasure I experienced when first I saw 

 the little animal, the subject of my present notes. It was a 

 diminutive Eodent, of the genus Lagomys, and, as its name 

 implies (lagos, a hare, mus, a mouse), being a sort of inter- 

 mediate link between the hares proper and the guinea-pigs. 



All the known species of the genus are entirely confined to 

 the northern parts of the world ; four species are all that have 

 hitherto been described. One, the Pika, or Sadajack, from 

 Siberia ; one from Mongolian Tartary ; a third from the 

 north-eastern part of Russia ; the fourth from the Rocky 

 Mountains. 



The general appearance of the Pikas is more suggestive 01 

 a guinea-pig {Gavia) than a hare. The (Gavia Australia) com- 

 mon in the mountain regions of Uspallata, is named the moun- 

 tain rabbit, from its close external resemblance to that animal. 

 But there are important and well-defined structural differences 

 between Lagomys and the hares — the skull in the Pika is 

 more depressed and broader behind; the supra-orbital pro- 

 cess is wanting ; the orbits are differently shaped, and the 

 malar bone reaches nearly to the auditory opening ; instead of 

 the cribriform arrangement in the nasal process of the supe- 

 rior max bone, as in hares and rabbits, there is in Lagomys 

 but one large opening. In Lagomys the vomer joins the 

 anterior sphenoid; but in hares, these bones are separated 

 by an oblong opening. The upper incisors are broad, each 

 tooth having a vertical groove on the outer side ; the lower 

 incisors are much smaller than the upper. The molars are 

 much the same as in hares, with transverse ridges of enamel. 

 There are other slight differences, but not of sufficient impor- 

 tance to need mention here. 



Of their habits nothing hitherto seems to Lave been 

 known, and as I have only to introduce the two species found 

 on the Cascade and Rocky Mountains — one, a new species, 

 discovered by myself, and named (Lagomys minimus, Lord), 

 the other, previously described by Sir John Richardson — I 

 shall relate the story of my finding them. 



In the summer of 1858 I set out on a collecting and hunt- 

 ing expedition from Fort Colville, one of the early trading 

 posts of the Hudson's Bay Company, situated in a beautiful 

 valley on the upper part of the Columbia river, my object to 

 ascend the Cascade range of mountains. My route to follow 

 up the Na-hoil-a-pitqua river, and then to strike across the 

 Osoyoos lakes, and keep along the banks of the great Shi- 

 milkameen river, to strike Ashtnolow, a tributary that led up 

 into the mountains, the course of which I was to follow as far 

 as practicable. I had a delightful trip through a district inde- 

 scribably lovely. 



