2IO Bulletin American Museum of Natural History. [Vol. XXII, 



to which on the following page he gave the name colima." On a 

 casual consideration of the case with Mr. Bailey in Washington 

 just before the publication of his paper, I assented that his interpre- 

 tation of the matter was probably correct, but now on reexamination 

 of the subject, in the light of 70 specimens of colima before me and 

 4 of mascotensis, I find the type of the latter is not referable to colimcz 

 but to the species he has kindly named in my honor, so that 5. alleni 

 is beyond question a synonym of mascotensis. My original descrip- 

 tions, as well as the types and cotypes, show clearly the strongly 

 marked differences between these two unusually distinct forms, for 

 members of this genus. 



The largest specimens of the present series (they are also very old, 

 as shown by the condition of the skull and teeth) equal or slightly 

 exceed in size Sigmodon hispidus major Bailey (type locality, Sierra 

 de Choix, 50 miles northeast of Choix, Sinaloa), the range of which is 

 given as "West coast of Mexico from Tepic to southern Sinaloa." I 

 can look upon these large specimens of the present series, however, 

 as merely old, very large examples. 



12. Oryzomys mexicanus mexicanus Allen. 



Thirty-eight specimens, 34 taken in the vicinity of Escuinapa, 

 Jan. 30, Feb. 4 and 19, and 4 from Los Limones, April 22-26. 



They are nearly all middle-aged or rather young, only two having 

 the teeth much worn. The 9 largest specimens, all males, measure: 

 Total length, 286 (257-305); head and body, 136 (127-146); tail 

 vertebrae, 148 (140-160); hind foot without claws, 28.5 (26-30.5); 

 ear from notch, 14.5 (12.7-16). 



13. Oryzomys melanotis Thomas. 



One specimen, Los Limones, altitude 3500 feet, April 24. 

 14. Reithrodontomys tenuis Allen. 



Twenty-four specimens: Escuinapa, 22 specimens (8 are in for- 

 malin), Jan. 12, 30, Feb. 5, 6, 15, May 27, 30, July 7, 20; Los Limones, 

 i specimen, April 25; Juan Lisiarraga Mountain, i specimen, April 

 30 (the last two are skins without skulls). Only 4 of the skulls have 

 worn teeth ; in all the others the tubercles of the crowns are wholly 

 unworn, and the pelage is softer, grayer, and less fulvous than in 

 the old adults with worn teeth. A litter of five quarter-grown young 

 are labelled as taken Jan. 12. 



