^4 PROCEEDINGS OP THE NATIONAL MUSEUM vol. 75 



There is little cranial variation also, save to some extent in the 

 shape of the posterior termination of the nasals. Skulls may be told 

 from those of confudarms chiefly by the extension in the former of 

 the temporal ridges as far as the interparietal. The rostrum also 

 averages more slender and the interpterygoid narrower. Average 

 measurements of five large specimens are : Head and body, 135 ; tailj 

 190; foot, 28; ear, 19; and length of skull, 35.8 mm. 



RATTUS EDWARDSI EDWARDS! (Thomas) 



Mus edwardsi Thomas, Proc. Zool. Soc. London, 1882, p. 587 (western Fukien, 

 China). 



Specimens. — Two from Kuatun, Fukien. 



These very large rats may be considered topotypical, and their 

 skulls measure 61 and 58 mm. in length. 



RATTUS EDWARDSI GIGAS (Satunin) 



Mus gigas Satunin, Ann. Mus. Zool. Acad. Imp. Sci. St. Petersb., vol. 7, 1903, 

 p. 562 ("Valley of Chodzigou, near Lunganfu, Szechwan, China). 



Specimens. — Two from southwest of Mount Omei, Szechwan. 



These two sx^ecimens are not distinguishable with certainty from 

 those of Fukien, but G. M. Allen considers gigas to be a valid race 

 and doubtless with adequate material differences would be readily 

 apparent. 



RATTUS LATOUCHEI (Thomas) 



Mus latouchei Thomas, Ann. Mag. Nat. Hist., ser. 6, vol. 20, 1897, p. 13 

 (Kuatuu, Fukien, China). 



Specimens. — Three : Mount Omei, Szechwan, 1 ; and 70 miles south- 

 west of Yenpingfu, Fukien, 2, 



One of the Fukien examples is but half grown and the dorsal 

 coloration is dark sooty with practically no vestige of brown — a type 

 of Juvenal coloration usual in cricetid rats but apparently rare in 

 murids. The head, however, has assumed the adult pelage. The 

 larger specimen measures; head and body, 252; tail, 334; foot, 52; 

 and ear, 35 mm. It shows a head coloration that is typical of the 

 species but the body color is evidently unusually dark, being without 

 white tips to any of the hairs. Most of the skull is broken but 

 there remains sufficient to show the cranial characters of latouchei, 

 consisting chiefly of the large size in connection with the fact that 

 the dentations of the premaxillary-frontal sutures do not extend 

 caudad of the posterior tips of the nasals. 



Perhaps the Szechwan specimen should be referred to mackenzii, 

 of which no examples are at hand, but the measurements (hind foot 

 57) are larger than are supposed to occur in that race, and both skin 

 and skull are practically indistinguishable from the Fukien adult. 



