﻿AFRICAN SILKWORM (ANAPHE INFRACTA, WLSM.) IN TJQANDA. 273 



mass of separate or loosely attached cocoons remains, the silk of which is the 

 least valuable. From them all the foreign matter and the cast skins of the 

 larvae and pupae should be removed. The silk of the three envelopes and 

 xhat of the cocoons should be kept separate, and after being pressed should be 

 packed for shipment in separate bales. 



In common with the Eri or Castor Silkworm (Attacus ricini), the silkworms of 

 the genus Anaphe have an immense advantage over the Mulberry Silkworm 

 (Bombyx mori\ in that the cocoons do not require to be " stifled," that is, killed, 

 to prevent the egress of the moth. 



With a view to obtaining supplies of wild silk, it would be advisable to draw 

 the attention of the natives to the fact that it is to their interest no longer to 

 destroy the nests of Anaphe. Indeed, the collecting and propagation of these 

 insects might well become a source of profit to them, as they would readily be 

 able to sell the nests, at a price fixed by agreement, to any company exploiting 

 this product. 



Natural Enemies. 



As might be expected from its manner of living in large colonies, A. infract a 

 does not enjoy a perfect exemption from predaceous or parasitic attack. The 

 insects and birds mentioned here as attacking the silkworm I collected in Bukoba 

 District, German East Africa, and in Uganda. 



Birds. — The chief predaceous enemies of this moth appear to be birds, of which 

 I have observed three species actually feeding on the larvae and have found the 

 insects in their stomachs : — Chrysococcyx cuprous (Golden Cuckoo), Pycnonotus 

 layardi (Layard's Bulbul ; Luganda, " Sosolia "), and Motacilla campestris 

 (Yellow Wagtail ; Luganda, " Kalisa "). Of these, Pycnonotus layardi is the 

 worst enemy. These birds, however, apparently attack the larvae only during 

 the first instar, before the appearance of the irritating hairs, which presumably 

 make the larvae distasteful or obnoxious. 



Parasitic Insects. — The silkworm is attacked by other insects in almost every 

 stage of its development. 



The eggs are attacked by a minute Chalcidid parasite, Tclenomus gowdeyi, 

 Crawford (subfamily Scelioninae), which I first discovered in Bukoba. At 

 first I considered this to be the most serious of the parasites which attack this 

 silkworm, but I have since found another new Chalcidid, Pleurotropis telenomi, 

 Crawford (subfamily Eulophinae), which in its turn parasitises T. gowdeyi. 

 This secondary parasite will probably maintain a balance between the primary 

 parasite and the host. 



From the cocoons two parasites have been bred, an as yet unidentified rly 

 (coll. no. 2315) of the family Tachinidae and Crypt us {Oneilella) formosus, 

 Brulle, a species of parasitic wasp of the family Ichneumonidae. C. for moans 

 is a shining blue-black insect, having the middle of the antennae banded with 

 white, the head and pronotum partly red, and the wings blue with a broad 

 hyaline band. This parasite pierces the nest with its ovipositor, laying its 

 eggs in the larvae of the silkworm, and the larvae of the Cryptus on hatching 

 feed on the larvae and pupae of the host, If the nests are collected from the 



