388 PROCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 



of the plants. They pupate in the affected stems and the moths emerge 

 through holes previously made by the larvae. (Plate 49, fig. 4.) 



The caterpillars have five brown stripes on a pale yellow body and 

 show no variation or change in appearance. 



Diatrcea venosata (C. S. 1607). 

 Plate 49, figs. 2,3 ; Plates 50, 51. 

 Foodplants — 

 Sugarcane. 

 Sudan grass. 



RarJii and Batri — [Saccharum spontaneum). 

 Juar — (Andropogon Sorghum) . 

 Ikri (Saccharum fuscum). 

 Bajrct {Pennisetum typhoideum). 

 All these foodplants have been recorded in the neighbourhood of 

 Pusa. The caterpillars occur largely in batri, Sudan grass and juar 

 and only occasionally in the other plants. 



The seasonal history of this species is more regular than that of 

 Chilo simplex and Diatrcea auricilia. Hibernation in the larval state 

 commences about September and continues up to March-April when 

 the over- wintering larvae pupate and emerge as adults. During the 

 active season the life-cycle occupies about five to seven weeks, viz., 

 egg about 6 days, larva about 21 to 30 days and pupa 9 to 11 days. 

 Eggs are deposited in the same manner as Chilo simplex. The caterpillars 

 feed inside the stem and have been observed to occur more in grown 

 plants than in young ones, many of them being found in individual 

 stems. Pupation takes place inside the tunnels in the affected stems. 

 This insect is a real pest of juar among the cultivated crops. 

 The caterpillars have large shining dark brown warts, usually with 

 broad pinkish stripes along the line of the trapezoidal and supra-spira- 

 cular warts. In some cases the stripes may be indistinct and in certain 

 other cases again the warts may be indistinct. In hibernating iarvee 

 both the stripes and warts may be indistinct. 



Diatrcea sp. (C. S. 1610).* 



Plates 52, 54, and 53, fig. 1. 



Foodplant — Sugarcane. 



This borer has so far been observed to be confined to Eastern Bengal 



and Assam, the western-most places where it has been found being 



Goalundo and Pabna. There has been no opportunity of investigating 



it properly. Therefore neither its seasonal history nor alternative 



* Since named by Sir George Hampson as Argyria tumidicosialis, Hmpsn. 



