No. 51 G] THE CUTICULA OF CESTODES 



707 



cells as conceived by Blochrqann and adopted by the au- 

 thors of these text-books. 



Fig. 2 from Hein (1904), who follows Blochmann 

 closely, shows the same relations in the digenetic trema- 

 todes. It will be seen in both these figures that the sub- 

 cuticular cells form a distinct although irregular layer 

 and are joined with the inner surface of the cuticula by 

 long projections. These Blochmann and Hein regard as 

 the ducts through which formative material is added to 



the cuticula, of which these cells are thus the matrix. It 

 will further be noticed in these figures that the sub- 

 cuticular cells apparently do not form a part of the paren- 

 chyma in which they lie, and also that among them are 

 sense cells and gland cells which are usually conceded to 

 have an epithelial origin. 



Another theorv of the cuticula which is not very differ- 

 ent from Blochmann >s is that of Brandes (1892), who 

 also considers the structure in question to be the product 

 of the subcuticular cells (Fig. 3). These, however, he 

 conceives to be single-celled glands which are joined with 



