ALIMENTAKY CANAL IN THE BEE 513 



are situated groups of smaller cells forming crypts which are 

 weakly developed in the bee. 



The cells of the latter are disposed in two or three layers 

 (PL 16, fig. 8 ; fig. 9, k). The deepest row situated on the 

 basal membrane is represented by the smallest cells (in the 

 section three or four of them are visible), covered above and 

 laterally by larger cells bordering directly on the epithelium 

 of the folds of the stomach (PI. 16, fig. 11, k). In general the 

 protoplasm of the cells of the crypts are more basophil than 

 the stomach epithelium (PI. 16, fig. 11, k, d). The nuclei of the 

 cryptic cells are large and poor in chromatin. As described by 

 Petersen we did not succeed in observing their karyokinesis. 

 Nasonov (1898), however, observed the process of division of 

 the nuclei in these cells. 



The cryptal cells present the sources from which the stomach 

 epithelium is newly formed. Besides, their cells seem to 

 produce a secretion themselves as well. The following facts 

 confirm this supposition. The most superficial cells of the 

 cryptal are not adjacent to each other with their apices, so 

 that there remains an ovoid lumen between them in the shape 

 of a vacuole filled up with a drop of homogeneous secretion 

 staining pink with Giemsa's stain (PI. 16, fig. l,k; fig. 11, vc). 

 Besides, there is also observed an accumulation of secretion 

 above the crypta which is revealed by displacement to the sides 

 of the ' hairs ' of the superficial band of the stomach epithelium 

 (PI. 16, fig. 9, fe). 



In general the secretory processes in the stomach of the bee 

 take the following course : 



(1) Separation of the peritrophic membrane (PI. 16, fig. 6,2? ; 

 fig. 9, 'p), (2) production of secretion by the surface of the 

 glandular cells, (3) severance of the superficial portions of the 

 epithelial cells (PI. 16, fig. 8, d), and (4) separation of a homo- 

 geneous secretion by the cryptic cells (PI. 16, fig. \\,vc). 



(c) The epithelium of the stomach lies on a basal membrane 

 clothed exteriorly by a transversely striated muscular mem- 

 brane, the muscle-fibres of which are very rich in sarcoplasm. 

 The muscle-fibrils are disposed in bundles occupying the greater 



