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CHAPTER V. 



The Anatomy of the Pupa. 



The following account is derived from the late Dr. C. 

 Herbert Hurst's excellent paper on the subject, published 

 in the " Studies from the Biolog. Lab , Owens College," II., 

 1890, pp. 47, et seq. 



The paper is too full to be reproduced in full in an 

 introduction like the present, but is characterised through- 

 out by the most painstaking accuracy, and I have been 

 able to verify most of the statements reproduced. 



During the latter stages of larval life, in addition to the 

 visible head appendages, there appear eight other pairs 

 beneath the larval cuticle. Of these six are thoracic and 

 two abdominal. The thoracic pairs are three of them 

 dorsal, the future pupal syphons, the wings, and the 

 halteres ; and three pairs ventral, the future legs. The 

 two abdominal pairs belong to the last two segments. 

 Those of the eighth lie in the larval syphon, and are to 

 form the fins of the pupa ; the hindmost pair form the 

 outer gonapophyses of the adult, which are accessory organs 

 of copulation. 



All these eight pairs arise as foldings of the epidermis 

 (" hypodermis ") outwards, and are quite hidden under 

 the larval cuticle. The antennae, too, are much larger in 

 an advanced larva than they appear to be externally, as the 

 growing basal portion is folded, or even telescoped beneath 

 the unyielding cuticle. Towards the end of larval life the 

 animal becomes sluggish ; profound changes in the mouth 

 parts deprive it of the power of eating, and it floats with 

 its breathing tube at the surface. Shortly, the cuticle 

 bursts in the thoracic region, the pupal respiratory 



