CIRCULATION IN INSECTS. 



237 



muscular apparatus which surrounds it, seen 

 from the lower side. In the last of these figures, 



33c 



A is the tapering prolongation of the tube, pro- 

 ceeding towards the head of the insect ; v, one of 

 the dilated portions, or ventricles, as they have 

 been called, of the dorsal part of the tube ; f, one 

 of the small tendinous folds, to which the liga- 

 mentary bands are attached ; and l is one of 

 these bands, having a triangular, or, if considered 

 as continuous with that on the other side of the 

 vessel, a rhomboidal shape, and attached at r, 



