BUTTERFLIES OF MOUNT PENRISSEN. 29 



A List of the Butterflies of Mt. Penrissen, 



Sarawak, with Notes on the Species. 



By R. Shelford. 



The species here noted were obtained in May 181)9, at 

 elevations varying from 2,800 to 4,200 feet, and though I have 

 no doubt that collecting- at different times of the year would 

 reveal the presence of a few more species, the present list may 

 be regarded as fairly complete. Butterflies on Penrissen were 

 not nearly so numerous as they are at all times of the year on 

 the mountains near Kuching, Mts. Matang and Santubong ; the 

 very rank and dense jungle of Penrissen and the total absence of 

 cleared spaces such as occur on the two latter mountains no 

 doubt account for this comparative scarcity ; at the same time it 

 should be noted that the collection now described, contains 

 several species which have never, in spite of the most careful and 

 frequent collecting, been recorded from Matang and Santubong, 

 and these species give quite a distinctive character to the collec- 

 tion. The insect fauna of a mountain possesses all the characteris- 

 tics of an insular fauna consisting of 



(1) widely ranging low-country species (comparable with the 



continental species of an insular fauna). 



(2) species closely allied to. perhaps merely varieties of the 



above, but constant in their differences and mountain 

 habitats. 



(3) widely ranging mountain species of common occurrence on 



most mountains, of very rare occurrence in low-country, 

 (comparable with insular species occasionally found on 

 ther continental areas). 



* Novitates Zoologicae Vol. VI. No. 2 fl899) contains an interesting 

 paper of the birds of the Galapagos Islands by Rothschild "and,' Hartert the 

 distribution of the species there recorded is closely parallel by the distribu- 

 tion of the insects of Bornean Mountains. 



