240 MR. R. I. roCOCK ON THE 



African geneiu of the family by their ears, feet, fur, and the 

 additional tuft of superciliary vibrissfe, and by the cranial 

 characters pointed out by Thomas in his paper on African 

 Squirrels. 



Subfamily Marmotin^. 



Grlans penis, at least in Marmota and Cynomys, very small, a 

 diminutive copiy indeed of that of Fanambitlus but with the point 

 not upturned by the curvature of the baculum ; also somewhat 

 resembling that of Funisciuriis and Paraxerus, except that the 

 proximal thickening and the terminal narrowed piece are 

 structurally simple and less sharply diiierentiated. Baculum 

 also relatively very small, highly specialised with a symmetrical 

 terminal, denticulated lamina in Citelhis, but ending simply with 

 a few irregularly placed denticles in Ilarinota and Cynomys. 



Ears simplified, without tragal or antitragal thickenings, but 

 with a hairy expansion of the anterior rim extending into the 

 cavity baneath the supratragus. 



Feet with fossorial claws and the third digit not shorter than 

 the foui'th. 



Genera : Marmota, Marmotops, Cynomys, Citelhis with many 



subgenera, ? 2'amias, and Eutamias. 

 Distribution. Holarctic Region. 



Although admitted as a subfamily in many text-books, this 

 group was not granted tha.t rank by some competent judges, 

 e. g. Forsyth Major and Miller, on account of the closeness of 

 its kinship with the true Squirrels. It appears, hoAvever, to be 

 sufficiently well characterised to be admitted. 



I have provisionally included Tamias and Etitamias mainly on 

 the strength of Tullberg's statement that the genitalia are similar 

 to those of Marmota, but also because Tamias and Citellus are 

 alike in the presence of large cheek-pouches, a character in 

 which they difier from all the typical Squirrels. 



Nevertheless the feet of the only example of this group I 

 haye seen in a fresh state, namely a female of Eutamias quadri- 

 I'ittatus, are not like those of Citellus, and hardly differ from 

 those of the Squirrels, The ears, too, do not show the special 

 features characteristic of those of Citellus, Marmota, and Cynomys, 

 but are more like those of Sciurus. More extended observations 

 on the two genera are required to determine their exact 

 systematic status. Possibly they will prove to be worth ranking 

 as a special subfamily — Tamiinfe. 



7. The Flying Squirrels. 



The Petauristidaj wei^e classified by Thomas in 1908*. Setting 

 aside Petaurista, he took the genus Sciuropterus, already shown 

 by Heude and Forsyth Major to be composed of heterogeneous 



* Ann. Mag. Nat. Hist. (8) i. pp. 1-6. 



