ANATOMY OF THE CESTODES 



Cu. 



basal membrane and penetrate the internal surface of the cuticle 

 with small pistil-like enlargements ; at the internal surface of the 

 cuticle they spread out into a thin layer (fig. 118.) 



In addition to the above- 

 mentioned, there are other 

 cuticular formations occur- 

 ring on the cuticle of some 

 cestodes, such as immotile 

 little hairs and variously 

 formed hooks, such as are 

 seen principally on the scolex. 

 Their development is only 

 roughly known in a few 

 species ; they are usually 

 already present in the cysti- 

 cercus stage, and in the same 

 order and form as they are 

 found in the fully-developed 

 tape-worms ; systematically 

 this is of importance, be- 

 cause by these structures 

 cysticerci can be recognised 

 as belonging to certain 

 species of tape- worms. 



The CUTICULAR GLANDS 



in cestodes are scarce. 



The parenchyma forms the 

 chief tissue of the entire 

 body, and in all essentials 

 its structure is similar to 

 that of the Trematodes. 



In the, parenchyma of al- 

 most all the Cestodes there 

 is found in adult specimens, 

 as well as in cysticerci, light 

 refracting concentrically stri- 

 ated structures, of a spher- 

 ical or broad elliptical 

 shape, which, on account 

 of their containing carbo- 

 nate of lime, are termed CALCAREOUS BODIES (fig. 118, C.). Their 

 size varies according to the species between 0*003 and 0-030 mm. ; 



F.V.S. 



L.m 



FIG. 118. Schematic representation of a 

 small part of a transverse section of Ligula. 

 500/1. (After Blochmann.) Bs., Basal mem- 

 brane ; Cu., cuticle; at its base are the ter- 

 minal laminae of the sub-cuticular (epithelial) 

 cells ; in the centre there is a cuticular organ 

 of sense; F.v.s., follicle of vitelline ' sac ; Exc. 

 excretory vessel ; C., calcareous body ; L.m. 

 longitudinal muscles ; M.c., cell of muscular 

 formation ; P,m., parenchymatous or dorso- 

 ventral muscles ; PL, plexus of nerve-fibres ; 

 A.m., annular muscles ; Sc.c., sub-cuticulat 

 cell ; O.s., organ of sense ; T.c., terminal cell. 



