294 



COi\'^TROL OF M ATTLE I5AGW0RM. 



Our knowledge of the life-history of this parasite is as 

 yet incomplete. There seems to be two generations a year, for 

 fiill-growii larvae and also pupae were found in hags in March, 

 and eggs and young larvae in April. The period over which 

 the adults emerge is i)rolonged, and the two generations 

 overlap. Eecords made by Haines and myself show that adults 

 emerged continuously from March to October. Individuals 

 kept in cages and fed on honey and water have lived for two 

 to three months. Although numbers of bagworms were placed 

 in the cages with the parasites, on only one occasion did a 

 female oviposit in one of the bags, and I was fortunate enough to 

 witness the event. She thrust her ovipositor through the sides 

 of the bag from two or three different positions, and then left 

 it. The whole process occupied less than three minutes. On 

 opening the bag the contained larva was found to be limp and 

 apparently dead, and a large yellow egg (Fig. 4) was found 

 adhering to the side of the bag. This egg hatched in three 

 days, but unfortunately the young larva (Fig. 5) died soon 

 after it was hatched. 



fic,^ 



Fig. 2. — Philopsijche ahdominali.'^, Morley. Mature larva. 

 Fig. 3. — Fhilopsychr abdoininnUs, Morley. Piipa, female. 



The larva is an external parasite throughout its life, and 

 can move freely in the bag. It does this by means of the rows 

 of curved spines which arm the dorsum of each of the 

 abdominal segments (Figs. 2 and 7). These spines catch in 

 the silken sides of the bag and also serve to hold it securely 

 in position w^hilst feeding. The mandibles are well developed, 

 simple, and taper to a sharp point (Fig. 6). In the mature 

 larva they measure 70 jn in length by 30 /jl across the base. 

 The chitinised framework of the mouth-parts and the pigment 

 spots on the head of this larva are peculiar and enable one 

 to recognise it readily (Fig. 8). 



