378 Mr. O. Thomas on 



has been patched at some time. The T. hrigilta group is 

 so characteristically different in pattern from the T. hecabe 

 group, that my explanation seems infinitely more probable 

 than that a form having the pattern of T. Boisdavaliana ? , 

 but (unlike all other species of the genus) having botii sexes 

 coloured pale yellow, should suddenly appear in the midst 

 of the T. hrigitta group. I believe T. Impale to be distinct 

 from T. floricola^ but to be a very nearly related species. 



35. GatopsiUa fiorella, Fabr. 



J , S.S. ' Kaiser,' off Zanzibar Island, 20th March ; be- 

 tween Katunga and Mandala, 8th April ; c? c? ? ? , Mandala, 

 10th and 11th April, 1899. 



36. Papilio demodicusy Esper. 



Chinde, 29th March, 1899 ; caught near the bank of tlie 

 Zambesi. 



Hesperiidae. 



37. Parosmodes icteria^ Mabille. 



Between Katunga and Mandala, 8th April ; Mandala, 

 10th and 11th April, 1899. 



38. Baoris fatuelluSj Hopffer. 

 Mandala, 11th April, 1899. 



39. Rhopalocamptaforestany Cramer. 

 Mandala, lUh April, 1899. 



XLIII. — Descriptions of new Rodents from the Orinoco and 

 Ecuador. By Oldfield Thomas. 



Rliipidomys marmosurus, sp. n. 



Size medium. Fur close, rather less woolly and more 

 Oryzomys-Yike than in typical Rhipidomys ; the hairs about 

 8-9 millim. long on the back. General colour above rich 

 reddish fulvous, finely lined with black. Head paler and 

 greyer, no definite face-markings. Ears large, with but little 

 anterior basal projection; their backs thinly haired, black, 

 contrasting markedly with the general colour. Sides paler 



