MUSEUM OF COMPARATIVE ZOOLOGY. 181 



Several specimens were obtained, corresponding in size and color 

 with what LeConte and Baird have described under this name. It is 

 apparently common. As I have previously stated elsewhere,* these Flor- 

 ida specimens have well-developed cheek-pouches. 



The specimens in question arc rather larger than any examples of 77. 

 leucopus I have seen from the Northern States, they agreeing very well in 

 measurements with the two specimens cited by Professor Baird. j The 

 large size of these specimens, conjoined -with their southern habitat, would 

 seem at first to clearly indicate their being distinct from II. leucopus, as 

 they are at least one third larger than the average size of the latter at the 

 North. Professor Baird in speaking of this species observes : " There is 

 every reason to consider this mouse as specifically distinct from II. leuco- 

 pus of the North; although skins, when much stretched (as Nos. 1105, 

 1112. from Middleboro', Massachusetts), of the latter, may measure as 

 much as those recorded here, yet they are certainly actually smaller, as 

 shown by the feet, which never attain anything of the length of .45 for the 

 anterior and .90 for the posterior." But he is " hardly satisfied," he adds, 

 " that this animal is different from the smaller 27. leucopus, as the differ- 

 ence in size is no greater than is to be seen in a series of Hesperomys from 

 more northern localities. The tail is duskier beneath than in 77. cognatus, 

 and the sides more rusty ; otherwise I can realize only the larger size. 

 Should both [77. cognatus and II. gossypinus'] prove to be the same, the 

 name 77. gossypinus must of course take precedence."' 



As already observed, the prevailing form of the Hesperomys of East 

 Florida is not essentially different from a large proportion of the 77. 

 leucopus of the North, either in measurements, proportions, or color, 

 although it is unmistakably referable to the so-called 77. cognatus, which 

 has been supposed to replace in the Southern Atlantic and Gulf States the 

 77. leucopus of the nmre northern ones. If, as I have elsewhere suggested 

 (Joe. cit.), as Professor Baird admits may be, and as the facts seem to indi- 

 cate, 77. gossypinus is inseparable from 77. cognatus, and the latter being 

 most unquestionably referable to II. leucopus, it would seem that 77. gos- 

 sypinus must also be referred to the II. leucopus. 



Respecting the variations in this species and the affinities of the 77. 

 gossypinus, Audubon and Bachman observe as follows: " That a species so 

 widely distributed and subject to so many variations in size, length of 

 tail, and color, should have been often described under different names is 

 not surprising. We have ourselves often been in a state of doubt on 

 obtaining some striking variety. The name Hypudccus gossypinus of our 



* Bulletin Mus. Comp. Zobl., Vol. I, No. 8, p. 229, 1869. 

 t Mam. X. Am., p. 469. 



