RESULTS FROM GIPSY MOTH PARASITE LABORATORY, 



head. Below the mandibles is a more or less circular labium with 

 heavily chitinized margins, supported by two short transverse ridges. 

 The mouth opening is small and hardly distinguishable, but prob- 

 ably lies directly beneath the tips of the mandibles, toward which 



Pig. 40. — Limnerhim ralulum: Third-stage larva. Enlarged about S times. (Original.) 



point there is a gentle declivity. Just in front of the deeply con- 

 cave, anterior end of the labium, in fact at the bottom of this con- 

 cavity, is located the external opening of the sericteries. Above the 

 mandibles are two large, circular, slightly pigmented spots, which 



undoubtedly mark the place 

 where the compound eyes 

 of the adult are beginning 

 to develop. 



FEEDING HABITS OF THE IMPRIS- 

 ONKD LARVA. 



With a clear understand- 

 ing of the mouth structures 

 in the three stages, we may 

 briefly consider the feeding- 

 habits of the imprisoned 

 larva. The old accepted 

 theory up to the time of 

 Eatzeburg was that in- 

 ternal parasitic larvje feed 

 upon the fat-body of the 

 host. Ratzeburg (1844), 

 however, was forced to replace this theory with one that is prob- 

 ably more nearly correct. He concluded that such larva3 feed 

 upon the l3anph and blood of the host rather than upon any of 

 the solid tissues. This view seems especially applicable to the feed- 

 ing habits of Apanteles and related genera, which often leave the 

 host in a living though comatose condition, but as the mandibles are 



Fig. 41. — Limneriutn ralidum: Anterior view of 

 liead of tliird-stage larva, showing mouthparts. 

 Enlarged about 60 times. (Original.) 



