]^2 SIXTH REPORT — 1836. 



portant to the interests of science. A correct knowledge of the 

 species is clearly the first point to be attained, being indispen- 

 sable for the due discussion of the other subjects embraced by 

 a local fauna^ but though this has formed the chief aim of the 

 works hitherto devoted to North American zoology, great un- 

 certainty still exists as to many species, the original descrip- 

 tions being so obscure that they do not enable us to recognise 

 the animals ; and even the commonest quadrupeds, about whose 

 identity, when found in certain localities, there can be no doubt, 

 have in very few instances, indeed, been satisfactorily compared 

 with the analogous ones inhabiting distant districts of America 

 or belonging to the old world. A critical review of the various 

 opinions entertained by zoologists respecting the several species, 

 (such as that which the Prince of Musignano has instituted in 

 his observations on Wilson's Ornithology,) would be obviously of 

 great utility, but want of space excludes it from this report, 

 wherein the Mammalia alone will be noticed in detail. The pre- 

 ference is given to this order, partly because, the number of spe- 

 cies being small, individual notices can be compressed within 

 reasonable limits, but chiefly because opinions are more various 

 concerning the quadrupeds than respecting the contents of the 

 other orders. A sketch of the labours of the different authors 

 who have brought North American zoology to its present state 

 might have been introduced, but its utility would not compensate 

 for the space it would occupy, and the task has been already to 

 a certain extent executed in the introductions to the several vo- 

 lumes of the Fauna Boreali- Americana. The reader is therefore 

 referred to that woi'k, to the American Natural History of 

 Dr. Godman, the Fauna Americana of Dr. Harlan, and espe- 

 cially to Pennant's Arctic Zoology, which contains ample re- 

 ferences to all the older writers. Fischer's Synopsis Mammalitim 

 is a good book of reference for the published species of Mam- 

 malia up to the year 1828. 



Previous to entering upon the details of the report, it is ne- 

 cessary to state that in it the term of North America is re- 

 stricted to that part of the continent which lies north of the 

 tropic of Cancer, thus including New Mexico, the Peninsulas of 

 Florida and California, and as nearly as may be meeting the 

 limits of the very different and peculiar South American zoolo- 

 gical province. In considering Mexico as the region in which 

 the Northern and Southern American faunae meet and mingle, I 

 follow the opinions of Professor Lichtenstein * and Mr. Swain- 



* " Erlautcrungcn dcr Nachiichtcn dcs Franc. Hernandez von den vierfus- 

 sigen Thicren Ncuspauicns, von Herr Lichtenstein." Gelesen m der Aka- 

 demie der Wissenschaften am 28 Jun. 1827. Berlin. 



