18 Merriam Mammals from Tres Marias Islands, 



but at present a rocky point on the northwest side, and a jutting reef on 

 the south side of Maria Magdalena Island, and some islets off the west 

 shore of Maria Cleofa, are the landing places used by the remnants of the 

 considerable number that once lived here. They are doubtless doomed 

 to speedy extinction." 



Rhogeessa parvula H. Allen. Tres Marias Rhogeessa. 



Rhogeessa parvula H. Allen, Proc. Acad. Nat. Sci. Phila., 285, 1866. Type 

 from Tres Marias Ids., Mexico. 



A single badly mutilated specimen of this little known bat was shot on 

 Maria Madre Id., where, according to Mr. Nelson's notes, it is " not un 

 common in the forest." 



Myotis nigricans (Maximilian). Maximilian's Black Bat. 



Mr. Thomas states that " a specimen of this species was obtained by 

 Mr. Forrer in the Tres Marias Islands." (Biologia Central!- Americana, 

 Mammalia, 206. 1881.) 



Otopterus mexicanus (Saussure). Big-eared Bat. 



Macrotus mexicanus Saussure, Rev. et Mag. de Zool., 2e ser. XII, 486-487, 

 1860. Type from Yautepec, Morelos, Mexico. 



This large long-eared bat is very common on Maria Madre Id., where 

 Mr. Nelson collected 52 specimens. He found it in the daytime in two 

 or three caves, and also in an old unused warehouse. The females were 

 heavy with young at the time of his visit (May, 1897). I have compared 

 Mr. Nelson's Tres Marias specimens with specimens collected by him 

 near the type locality of Saussure' s l Macrotus mexicanus' in the State of 

 Morelos, Mexico, and find no tangible differences except that the ears of 

 the island specimens are slightly the larger. I have also compared both 

 series with a fine series of topotypes of Otopterus bnlleri (H. Allen) from 

 Bolaiios, Jalisco, and am unable to find any characters on which the 

 latter form can stand. 



Glossophaga mutica sp. nov. Tres Marias Glossophaga. 



Type from Maria Madre Id. , Tres Marias Ids. , Mexico. No. 89271 $ ad. , 

 U. S. Nat. Mus., Biological Survey Coll. Collected May 8, 1897, by E. W. 

 Nelson and E. A. Goldman. Grig. No. 10976. 



Characters. Similar to G. soricina (Pallas) and G. truei H. Allen, but 

 differing in proportions and color reddish brown instead of gray or 

 sooty. 



Color. Fur of upper parts with basal | dull white ; apical J dull cinna 

 mon brown ; underparts similar but much paler. 



Cranial and dental characters. In the absence of authentic skulls of 

 G. soricina and truei for comparison it is impossible to differentiate the 

 cranial characters of G. mutica. The rostrum is rather broad, flat, and 

 swollen ; a rounded protuberance over each orbit marks the junction of 

 the rostrum with the braincase ; the braincase is abruptly elevated and 



