INTERNAL ANATOMY OF INSECTS. 105 
it expands into a blind sac having no connexion with 
the stomach ; so that the fluid food, as blood, &c. stored 
in it, must be regurgitated into the mouth before it can 
pass into that organ 3 . Thus these animals, besides their 
stomach, have a reservoir in which to store up their 
food; the product therefore of a single meal will require 
several days to digest it. 
2. The stomach (Ventriculus b ) is that part of the in- 
testinal canal immediately above the bile-vessels, which 
receives the food from the gullet for digestion, and trans- 
mits it when digested to the lower intestines . By its 
admixture with the gastric juice, the food acquires in 
the stomach a quite different colour from what it had in 
the gullet. In herbivorous insects it contains no acid, 
but, like the gastric juice of herbivorous quadrupeds, is of 
an alkaline nature d . The chyle is forced through this 
organ, probably in part by the pressure of the muscular 
fibres during the peristaltic motion ; and being pressed 
through the inner skin, is first collected in the interme- 
diate cellular part, and ultimately forced through the 
outer skin e . At its posterior end it terminates in the 
pylorus, a fleshy ring or sphincter formed of annular 
muscular fibres f . The stomach often consists of two 
or more successive divisions, which are separated from 
each other, and are often of an entirely different confor- 
mation and shape g . In the Orthoptera, Predaceous 
Coleoptcra, and several other insects, an organ of this 
3 Ramdohr Anat. 11—. b Plate XXI. Fig. 3. d. 
c Ramdohr Ibid. 28—. 
d Hercld {Schmetterl. 24) says that Ramdohr is mistaken here, and 
denies the existence of this juice in insects ; but as Ramdohr's re- 
searches were so widely extended, he is most likely to be right. 
c Ramdohr Ibid. 29. f Ibid. 31. s Ibid. 28, 
