Mammals from Bolivia. 131 



12. Neacomys spinosuSy Tlios. 

 2 ? . Cliaiuplaya, 1300 m. 20th May, 7tli June, 1901. 



13. rhyllotis Wolffsohnij sp. n. 



2 ? . Tapacari, 3000 m. 23rd March, 1901. 



? & young. Cochabamba, 2600 in. 22nd April, 1901. 



rii. Darwini fjroup. 



General appearance not unlike that of the true Ph. Dar- 

 xoini of Valparaiso, but softer furred and with longer tail. 

 Hairs of back about 13-14 tnillim. in length. General colour 

 above dull greyish fulvous, the tips of the hairs blackish. 

 Sides clearer and more bufFy. Under surface sharply defitiefl 

 white, the bases of the hairs slaty grey, even on the chin and 

 throat. Hands and feet pure white above. Tail long, well- 

 haired, but not pencilled, brown above and whitish below, 

 but the contrast not so marked as in Eligniodqntia domonim. 



Skull markedly different in shape from that of Ph. Dar^ 

 ivini; the brain-case longer and narrower, the posterior inter- 

 orbital region much more expanded, with marked divergent 

 supraorbital ridges commencing halfway along the interorbital 

 space. Nasals long and broad. Palatal foramina large and 

 open, reaching to the first third of in\ BulUe much smaller 

 than in Ph. Dai'toini. Molars comparaiively large and 

 heavy. 



Dimensions of the type : — 



Head and body 125 millim. ; tail 1-44: j hind foot (s. u.) 28 ; 

 ear 25. 



Skull : greatest length 32 ; basilar length 25 ; zygomatic 

 breadth 16 ; nasals 13*4 X 4*9 ; interorbital breadth 4'4 ; 

 breadth of brain-case 13*1; palate length 14; diastema 85; 

 palatal foramina 8x 2'7 ; length of upper molar series 5'4. 



JIab. Tapacari, 3000 m. 



Type. Old female. B.M. no. 1. 1. 1. 59. Original num- 

 ber 1390. Collected 23rd March, 1901. 



1 have named this handsome species in honour of my friend 

 Mr. J. A. WolfFsohn, to whose generosity the British Museum 

 is indebted for series of all the mamnials of V^alparaiso. 

 His specimens of the true Ph. Darwini have been of especial 

 service in the present connexion. 



The striking difference in the shape of the interorbital 

 region will readily distinguish this species from all its allies. 



14. Phyllotis lutescens, sp, n. 



2 ? . Choquecamate, 4000 m. 14fh to 16th July, lUOl. 



