(se; 



FIGURES 28-32. Stomodaeum of Hydropsyche sp.: 



28 — longitudinal section through the end of esophagus, proventriculus, cardiac 

 fold and beginning of the midgut; 29 — spinules on the walls of the esophagus; 

 30 — sclerites of the proventriculus; 31 — "teeth" of the proventriculus; 32 — 

 cross section of the wall of the proventriculus (29 — after Vorhies, 28, 30—32 — 

 after Noyes). 



It - large tooth, t — teeth, cf - cardiac fold, st — small tooth, es — esopha- 

 gus, lm — longitudinal musculature, prov — proventriculus, mes — mesenteron, 

 cir — circular musculature, ep — epithelium. 



32 



