VOL. XIII, PP. 137-150 APRIL 21, 1900 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



SEVEN NEW RATS COLLECTED BY DR. W. L. 

 ABBOTT IN SI AM.* 



BY GERRIT S. MILLER, JK. 



Among the mammals collected by Dr. W. L. Abbott during 

 a second expedition to Siam, and presented to the United States 

 National Museum are seven large and medium sized species of 

 Mus, all of which appear to be new. They were secured in 

 the mountains of Trong, a small state subject to Siam and sit 

 uated on the west side of the Malay Peninsula about 500 miles 

 north of Singapore. 



KEY TO THE RATS OF TRONG. f 



Hind foot about 50 mm.; skull about 55 mm. 



Tail much longer than head and body; back and sides 



strongly ochraceous Mus vociferans. 



Tail about equal to head and body; back and sides not 

 ochraceous. 



Fur composed almost exclusively of fine, grooved 

 bristles; ear longer than broad; general color 



above iron gray, beneath dull white Mus ferreocanus. 



Fur composed almost exclusively of coarse hairs, 

 with a very few slender grooved bristles inter 

 mixed; ear as broad as long; general color grizzled 

 brown above, pale buff below Mus validus. 



*Published here by permission of the Secretary of the Smithsonian 

 Institution, 

 f Exclusive of Mus 'alexandrmus.' 



31-BiOL. Soc. WASH. VOL. XIII, 1900. (137) 



