60 PROCEEDINGS OF THE NATIONAL, MUSEUM vol. 73 



mens in the Paris Museum, G. S. Miller, jr., has said that there are 

 two mounted cotypes of this rat and that the measurements are: 

 head and body, 160 and 150 ; tail 100 and 96 ; and foot, 30 and 33 mm. 

 It is very probable that other Chinese rats have often been mis- 

 identified as this, which seems to be exceedingly rare in collections. 

 From R. r. alexandrinus its skull is distinguishable only by the fact 

 that in the latter the anterior portion of the nasals are usually abruptly 

 wider, the temporal ridging heavier, and incisive foramina broader; 

 but these details are not always uniform. The best criterion for 

 differentiating the two is the great difference in the length of the tail. 

 Some might therefore conclude that humiliatus should stand as a 

 subspecies R. rattus. And it really seems no more distant from 

 alexandrinus than it does from R. r. exiguus. I am inclined to be- 

 lieve, however, that although related most nearly to the rattus group, 

 humiliatus is specifically distinct and probably would not cross, under 

 normal conditions, with either of the two rats mentioned. Immature 

 skins of humiliatus may be difficult to distinguish from similar speci- 

 mens of R. noi^egicus, but in adults the silkj^ pelage of the former is 

 diagnostic. 



RATTUS HUMILIATUS INSOLATUS A. B. Howell 



Rattus humiliatus insoJattis A. B. Howell, Proc. Biol. Soc. Wash., vol. 40, 



1927, p. 44 (near Yenanfu, Sliensi, China). 



Specitnens. — Four from Shensi : Yenanfu, 3 (including the type) ; 

 and Yulinfu, 1. 



This is a rather large and pale race. 



RATTUS HUMILIATUS SOWERBYI A. B. Howell 



Rattus humiliatus sowerhyi A. B. Howell, Proc. Biol. Soc. Wash., vol. 41, 



1928, p. 42 (near Imienpo, north Kir in, Manchuria). 



/Specimens. — Two, including the type, from the type locality. 



This also is a large race, but dark and richly colored and with 

 the sootiness of the face pronounced. Superficially it is not unlike 

 R. norvegicus but the softness of the pelage is distinctive, at least in 

 adults. 



RATTUS FLAVIPECTUS (Milne-Edwards) 



Mus flavlpectus Milne-Edwards, Nouv. Arch. Mus. Hist. Nat., 7, 1871, p. 93 

 (Muping, Szechvpan, China). 



Specimens. — Forty-three: Foochow, 3; Kuliang. 2; Futsing, 4; 

 near Yenpingfu, 4; and YO miles southwest of Yenpingfu, Fukien, 1; 

 near Chinkiang, Y, and Shanghai, Kiangsu, 21; Canton, Kwang- 

 tung, 1 ; and Mount Omei, Szechwan, 1. 



The dorsal coloration of this series is rather uniform, but several 

 of the older individuals have a very few white hairs scattered over 



