ON NORTH AMERICAN ZOOLOGY. 155 



gossipiiia, which inhabits the southern states, we know no 

 more than the name. The sigtnodoii* hispidum is found on the 

 banks of the river St. John, which flows between Georgia and 

 Florida. The ferrugineum inhabits cotton-fields on the Mis- 

 sissippi. Fiber zibethicus ranges from the Arctic Sea nearly to 

 the Gulf of Mexico. 



Though the various species of arvicola differ in size, aspect, 

 and in the relative strength of their members, so as to be readily 

 distinguishable from each other when brought into apposi- 

 tion, it is very diflicult to frame specific characters by which 

 they can be recognised when apart; and it is not therefore 

 surprising that many nominal species should have been pro- 

 posed, and, what is equally adverse to the interests of science, 

 that many perfectly distinct animals should have been described 

 under a common name. Until a revision of the genus has been 

 accomplished, and American and European examples have been 

 accurately compared with each other, we cannot admit that any 

 one species is common to the two countries, as amjihibius has 

 been supposed to be. The majority of arvicolce in our list be- 

 long to the fur-countries, though some, as riparius andj-^eww- 

 sylvanicus, extend also far into the United States ; the latter is 

 the smallest as well as the most common American species. 

 A. rubricatus. distinguished by a bright red stripe on the flanks, 

 was seen by Mr. Collie in Behring's Straitsf. The georychi, 

 or lemmings, distinguished from the true meadow-mice by their 

 thumb-nails and extremely short tails, all belong to the north- 

 ern extremity of the continent, unless the very doubtful sjialax 

 vittatus of Rafinesque, found in Kentucky, shall be hereafter 

 discovered to belong to this genus. The mynomes pratensis of 

 Rafinesque requires further examination, as do also his lemmus 

 talpoides, albovittatus, and noveboracensis, indicated rather 

 than characterized in the American Monthly Magazine for 

 1820. 



Though the "gauffres", or pouched rats, abound in all the 

 prairie lands and sandy tracts of the United States, their hi- 

 story is still very obscure. The species, which are numerous, 

 have been mostly confounded with the ticcan of Hernandez,or the 

 bursarius of Shaw ; but various generic names have been pro- 

 posed, such as geomys, pseudostoma, aseomys, diplostoma, and 

 saccophoi'iis. The first figure of the Canada species published 

 by Major Davies in the Linnean Transactions, represents the 

 very large cheeks as filled from within and pendent externally, 



* This genus requires further examination. 



t yt. NuttalUi appears in Dr. Harlan's list, but we do not know its distinc- 

 tive characters nor its habitat. 



