346 LEWIS HEXRY COUGH. 



possibly present. Tlie plasma is finely granular, staining 

 readily with lifeniatoxylin. The nucleus is oval, clear, 

 surrounded by a distinct membrane, and contains a nucleolus 

 and usually four chromatin bodies. The nucleolus stains 

 differently to the chromatin bodies, my material being 

 mostly stained in to to Avith borax carmine, and stained in 

 section with Ehrlich's haematosylin, counter-stained with 

 orange G, the nucleolus staining reddish, the chromatin 

 blue. Whether conical or rounded towards the parenchyma, 

 each subcuticular cell gives off one or more fibrillar processes, 

 which run inwards ; the processes from several adjacent cells 

 usually converge and collectively join the dorso-ventral 

 muscles, where those muscles break through the longitudinal 

 muscle (fig. 20). The subcuticular cells on the extreme 

 lateral margin also behave in the same manner, only that they 

 join the transverse muscle. Towards the lateral margins the 

 connection between the dorsal or ventral subcuticular cells 

 and the muscles is even more apparent, as the cells lie 

 grouped around the base of the muscles, the subcuticular 

 elements belonging to any one of the outer dorso-ventral 

 muscles all lying lateral to their muscle, thus assuming a 

 direction oblique to the cuticula. 



I have been able to verify this connection between sub- 

 cuticular cells and muscles in Dipylidium, T tenia, 

 Dibothriocephalus and Tritenophorus. The sub- 

 cuticular cells consequently belong to the dorso- 

 ventral and transverse muscle systems. In well 

 preserved material it is possible to demonstrate this connec- 

 tion of muscles and subcuticula for every cell lying entirely 

 in the plane of the section. 



The question arises. Why have such processes not been 

 observed before ? In my opinion this is probably due to the 

 methods used for fixing and hardening, and to the necessity 

 to cut the sections in the plane of the cells. The subcuticular 

 cells appear to be very difficult to fix and harden satisfactorily, 

 Zenker's solution being the only one which has given me 

 such results as yet. The silver impregnation method em- 



