104 



BUTTERFLIES OF THARRAWADDY AND 

 THE PEGU YOMA. 



BY 



E. V. Ellis, I.F.S. 



With a Map, 



The accompanying list deals chiefly with butterflies caught in the 

 Tharrawaddy District, which lies on the western slopes of the Pegu 

 Yoma, but for the sake of completeness reference has been made to 

 others caught in Prome, Rangoon, Henzada and Toungoo Districts. 

 The Pegu Yoma forests seem to house an interesting set of but- 

 terflies, as they form the meeting place for Malayan and Assam 

 types, and yet they are isolated by paddy plains and big rivers on 

 both sides They begin at Rangoon and extend to Mt. Popa in 

 Meiktila, more or less. The jungles of the Tharrawaddy District are 

 chiefly at a low elevation, under 500 feet, but towards their Eastern 

 boundary they rise to 2,600 feet in the main ridge. There are 

 three main types of jungle, each inhabited by characteristic 

 insects : — 



i. Deciduous bamboo jungle, fairly dry in the hot weather. 



This covers 90 percent, of the area. 

 n. Evergreen jungle found in local patches near certain 



streams, very rich in species. 



Hi. " Indaing " jungle, low level gravel, etc., characterized by 



the presence of Dipterocarpus tuberculatus, the " In " 



tree. This is inhabited especially by Arhopala tounguva, 



hevdtsoni and centaurea and Elymnias tinctoria. 



Of the other districts mentioned, Prome adjoins Tharrawaddy on 



the north, and Toungoo adjoins it on the east, being on the 



opposite slope of the Yomas. Rangoon, situated at the tail 



of the Yoma, is surrounded by patches of evergreen forest in 



which rather more Malayan types appear. Henzada lies to the 



west across the Irrawaddy, and consists of broad and rather dry plains 



backing on to the hills of the Arakan Yoma which rises to 5,000 ft. 



The butterflies from the plain forests of Henzada are the same as 



those met with in Tharrawaddy plains forests, but the hill insects 



are rather different. 



The present list cannot pretend to be complete for such a wide 

 area as the Pegu Yoma, but it represents four years collecting in 

 Tharrawaddy, and should be fairly complete for that District. To 

 finish the Pegu Yoma butterflies more research is needed in the 

 moister forests on its eastern slopes in the Pegu and Toungoo 

 Districts. It is hoped that the present list will assist anyone engag- 

 ed on that work. Finally I must express my great obligation to 



