ON NORTH AMERICAN ZOOLOGY. 151 



number of species and variety of forms of its rodent animals ; 

 but they are still very imperfectly known, as their original de- 

 scribers have too frequently contented themselves with noticing 

 the colour of the fur and the length of the tail, disregarding os- 

 teological characters, and rarely noting the dentition, so that 

 many of the species enumerated in the American fauna are of un- 

 certain genera, and many nominal ones have been introduced. 

 The American naturalist who shall sedulously collect rodentia 

 from various parts of his country, and describe minutely their 

 characters, adding comparative notices of the species of each 

 genus, will confer a great obligation on the lovers of science. 

 Rafinesque has noticed a considerable number of animals of this 

 order, some of them so peculiarly striped that they could not 

 easily be mistaken vfere they to come under the observation of 

 another zoologist ; but in the instances in which his animals 

 have been traced he is found to be so often inaccurate, and his 

 generic characters are so generally imperfect, that science would 

 sustain little loss if his notices were expunged from our books of 

 natural history, were it not that they serve the purpose of inducing 

 search in the localities he points out. In the preceding list we 

 have omitted most of the doubtful species which have been ad- 

 mitted into the systems. 



Sciurus cinereus, which has a multitude of synonyms tacked 

 to it, inhabits most parts of the United States, being very abun- 

 dant in Carolina and Pennsylvania. Sc. rufiventer of Geoffroy, 

 magnicaudatiis of Say, and ludoviciatms of Curtis, quoted by 

 Harlan, do not, as far as we can judge by the published descrip- 

 tions, differ from certain states of cinereus. A sc. hypoxaiithus 

 occurs in Lichtenstein's list of Deppe's Mexican animals ; but 

 no character is given, so that we have no means of ascertaining 

 in what respect it differs from the fulvous-bellied condition of 

 cinereus. The sc. capistratus, or fox-squirrel, is a larger spe- 

 cies, which varies greatly in its colours, and inhabits the middle 

 and southern states of the Union : it is generally supposed to 

 be one of the Mexican squirrels described by Hernandez, and 

 named by some authors variegatus, but this wants confirmation. 

 Say's sc. grammurus lives in holes, does not voluntarily ascend 

 trees, and has very coarse fur ; hence it is most probably a 

 spermophile : it was found near the sources of the Arkansa. 

 The black squirrels of the United States are generally referred 

 to capistratus ; but a smaller and totally black species (having no 

 white muzzle) inhabits the northern shores of Lake Huron, and 

 to this we have restricted the name of niger in the Fauna Boreali- 

 americatia. The larger black kind exists in Canada, and Her- 

 nandez mentions Mexican squirrels which are totally black, along 



