INTERNAL ANATOMY OF INSECTS. 119 
appendage of the gullet a ; and lastly, in the butterfly it 
appears as a large vesicle b ; the small intestine is grown 
very long c ; and the rectum has changed its form and ac- 
quired a caecum d . When we consider the adaptation of 
all these changes of form, the loss of old organs and the 
acquisition of new ones, to the new functions and mode 
of life of the animal, we see evidently the all-powerful 
hand of that Almighty Being who created the universe, 
upholding by his providence, and the law that he has 
given to every creature, the system that he at first brought 
into existence. 
We now come to the Diptcra. These have a very slen- 
der gullet, to which is attached on one side a long fili- 
form tube, terminating in the food-reservoir, which in 
some instances is simple e , but most generally consists of 
two or more vessels f , collapsing when empty, but vary- 
ing in shape and size when inflated with food : the mouth 
of the stomach in many cases is dilated into a kind of 
ringS; sometimes there is on each side a blind appendage 
or ccecum opening into it, in Bombylius covered with 
shags, which though not connected with the mouth by a 
tube, Ramdohr regards as saliva-reservoirs h ; in Muse a 
vomitoria the beginning of this organ below the mouth 
is covered with hemispherical prominences, and in Ti- 
pula it is dilated and marked with transverse folds. There 
are usually two pairs of bile-vessels ; in the Muscidec 
pedunculate and/r^e'; in Tipula, Bombylius, and Lcptis, 
a Plate XXX. Fig. 10. » Ibid. Fig. llvo. c Ibid, c, 
d Ibid. d. e Ramdohr, Ibid. t. xx./. 1. E.f. G. C. 
1 Ibid. t. xix./. 2. C.f. 3. CCD. t. xx./. 2. E. 
e Ibid. t. xix./. 2. D. 
" Ibid. t. xx./. 2. FF.f. G. DD. 184. 180.— 
' Ibid. I. xix./. 1. ON./. 2. OP.f. 3. F. t. xsviii./. 1, 2. p. 7. 
