Sesia tipuliformis and Trochilium apifonne, Linn. 189 



body, but the narrow hinder end opening into the vagina. 

 There is also a connecting canal extending from the middle 

 of the rece2)taculum semtnis, and opening into the efferent 

 channel of the copulatory pouch — the small round sac which 

 terminates in a separate external opening by" means of a 

 separate canal. 



The structure of the female reproductive organs exhibits 

 considerable development. It hardly differs from the usual 

 Lepidopterous type except in the absence of branching fatty 

 glands. There is, however, a very sliglit trace of deviation 

 from the normal type, seen in the imperfect development of 

 certain parts. 



Trochilium apiforme, Linn. 



The skeleton exhibits the same peculiarities of structure 

 which are characteristic of Sesia tipuliformis and scoliceformis. 



The nervous system likewise exhibits the same arrange- 

 ment, showing the remarkable arrest in the development of 

 the insect in tlie pupa state. There are nine ganglia — two 

 cephalic (supra- and infra-oesophageal), three thoracic, and four 

 abdominal, of which the last is the largest. 



The digestive system exhibits the following parts : — (1) 

 the oesophagus, (2) the crop, (3) the stomach, (4) the small 

 intestine, (5) the large intestine, provided with a blind branch 

 (the C£ecuni). The oesophagus is very long and narrow and 

 is enlarged at the lower end. The crop exhibits the dilata- 

 tion of the lower and lateral end of the oesophagus at its side, 

 as in the pupa. It remains in that condition when it changes 

 from the lower to the lateral position. The crop is narrower 

 and longer than in Sesia tipuliformis and scoliceformis, and 

 opens into the stomach by a short broad stalk. The re- 

 mainder is longer and narrower. The blind appendage is 

 comparatively short, but the large intestine, behind the 

 blind branch and the cgecum, is broad and thick, as in Sesia 

 tipuliformis and scoliaformis. 



The salivary glands are two long slender tubes, constructed 

 throughout exactly as in the two Sesiw, and opening into the 

 mouth in just the same way. 



The Malpighian vessels exhibit the typical structure. 

 There are three on each side of the intestine. Two of these 

 unite in a common canal, but the third joins them, and then 

 they all terminate in a common canal, opening at the com- 

 mencement of the small intestine. This common canal is 

 shorter, wider, and thicker than in S. tipuliformis. The 

 Malpighian vessels themselves are very long and sinuous 



Ann. & Mag. N. Hist. Ser. 6. Vol. vi. 14 



