Sesia tipuliformis and Trochilium apiforme, Linn . 189 
body, but the narrow hinder end opening into the vagina. 
There is also a connecting canal extending from the middle 
of the receptaculum seminis , 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 slight 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 the pupa state. There are nine ganglia — two 
cephalic (supra- and infra-cesophageal), 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 caecum) . 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 caecum, is broad and thick, as in Sesia 
tipuliformis and scoliceformis . 
The salivary glands are two long slender tubes, constructed 
throughout exactly as in the two Sesice , 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 
