410 THE ALIMENTARY CANAL OF THE IMAGO. 



rings, so that the basement membrane and epithelial coats 

 project between the muscle-fibres, and give it its characteristic 

 sacculated appearance. 



The sacculi or crypts formed in this way probably represent 

 the four blind glands of the larva. In many insects the whole 

 exterior of this part of the chyle stomach is covered by long 

 crypt-like glands, and the crypts are lined by true glandular 

 cells. I have sought in vain for gland cells in the rudimentary 

 crypts of the chyle stomach of Calliphora, such as Frenzel 

 figures from the chyle stomach of Blatta, Bombus and Hydro- 

 philus [130]. 



The epithelial coat of the caput and of the pyloric portion of 

 the chyle stomach consists of cubical rodded cells (see p. 279) 

 exactly like those of the lingual salivary glands. These I regard 

 as secreting cells, whilst the epithelium of the sacculated inter- 

 mediate region consists of large conical cells, which may be 

 compared to unicellular villi. These cells are united with 

 each other at their base only, which stains deeply ; the pro- 

 jecting conical portion of the cells stains less readily and 

 exhibits a transparent mucoid border, this is apparently shed 

 from time to time as a series of thin layers, which appear 

 as a spongy reticulum, in sections, separating the more solid 

 particles of food from the epithelium. I have never observed 

 vacuoles or granules of secretion in these cells, and I conclude 

 that they are concerned in the absorption of dissolved material, 

 peptones and carbo-hydrates. 



In the young imago and the nymph the cells of the inter- 

 mediate portion of the chyle stomach are not conical, but 

 columnar, and are covered by a thin layer of mucus. These 

 cells in imperfectly prepared sections often exhibit the goblet 

 condition, or the mucigenous portion of the cell may split into 

 rods, which sometimes give it the appearance of being ciliated. 

 I believe these appearances are the result of post-mortem 

 changes, due to imperfect fixation of the cells. 



The Proximal Intestine. In the Cockroach (Blatta) and in 

 many other insects the proximal intestine is not developed, or 

 is merely a part of the chyle stomach, so that it is usually 



