64 Zoological Society. 



with a pencil of hairs at the extremity ; this member being propor- 

 tionably longer, and the head much smaller and more elongated than 

 in G. Canadensis. The last-named species has been figured by the 

 late Professor B. T. Barton, in the Transactions of the American 

 Philosophical Society, also in the Encyclopedic M6thodique, but 

 was for the first time adequately described from living specimens in 

 the ' Fauna Americana,' p. 1 .">(;, when specimens were deposited in 

 the cabinet of the Academy of Natural Science of Philadelphia. 



" The subjects of the present memoir were placed in my hands 

 for description by Mr. Chaloner, a Member of the Academy. The 

 female is larger than the male, and of purer white beneath." 



The specimens of Gerbillus microcephalus above referred to, were 

 presented by Dr. Harlan to the Society ; and also a species of Sper- 

 mophilus, which Dr. Harlan exhibited to the Meeting. The last- 

 mentioned animal very closely resembles the S. Franklinii ; but 

 being of a much smaller size, Dr. Harlan was anxious that it should 

 be submitted to examination, and should be carefully compared with 

 that animal upon some future occasion. 



Several specimens of the Bean Goose (Anser secjetum), the Gray- 

 Lag Goose {Anser cinereus), the White-fronted Goose, (Anser albi- 

 frons), and of another species allied to these, were exhibited by Mr. 

 A.D. Bartlett, in order to illustrate a paper which he communicated 

 to the Meeting, "Ona new British species of the genus Anser, with 

 remarks on the nearly-allied species." 



" It may be necessary, before describing the new species," says 

 Mr. Bartlett, " to notice the three birds most nearly allied, in order 

 more clearly to point out the distinctions existing between them ; I 

 do this in consequence of the imperfect descriptions given by au- 

 thors, from which it is almost impossible to distinguish the species. 

 I shall commence with that which is the most common. 



" Anser segetum, Meyer. Bean Goose. Entire length, 33 inches ; 

 extent, 64; from the carpal joint to the end of wing, 19 inches. 

 The head and neck are brown, tinged with grey : back and scapulars, 

 darker brown, slightly tinged with grey, each feather being mar- 

 gined with greyish white ; primaries, dark brown, tinged with grey ; 

 shoulders of wings and secondary quill-feathers, greyish brown ; 

 rump, blackish brown ; upper tail-coverts, white ; tail, dark brown, 

 deeply edged with greyish white ; breast and belly, dirty white ; 

 abdomen and under tail-coverts, pure white ; bill, 2| inches long, 

 rather slender, flattened and narrow towards the tip ; the base, sides 

 and nail, black ; immediately above the nail commences a yellowish 

 orange mark, extending a little beyond the anterior margin of the 



