EXAMINATION OF HELMINTHES 



139 



sections from the posterior portion of the body in the neighbourhood 

 of the testes (fig. 61); from the hinder end of the anterior portion 

 in the neighbourhood of the ovary ; and one or more sagittal sections 

 taken in the median plane from the anterior body-half, showing the 

 oral sucker, pharynx, cirrhus pouch, and ventral sucker. One worm 

 divided transversely into two will supply these more important 

 sections, which should be carefully compared. The cuticle with its 

 armature should be noted, as well as the muscular structure and the 

 parenchyma. The student should then seek to identify the special 

 organs. In transverse sections taken at the level of the testes, the 

 stomach-tubes will be very noticeable, their side branches, which will 



if. 



Dst. 



CM, 



Exg. 



FIG. 61. Half of a transverse section from Fasciola hepalica, L., taken at the level of 

 the testes. 25 : 1. Cu., Cuticle with armature ; below it are the ring, longitudinal, and 

 transverse muscles. D., Stomach- tubes ; the hollow spaces are the blind branches of the 

 intestine which have been severed either diagonally or transversely. Dst., Yolk-gland 

 follicles. Exg., Excretory vessels. H., Branches of testes. Md., Median line. 



have been cut through either transversely or diagonally, appearing 

 as round or oblong cavities lined with a single layer of epithelium. 

 At both the dorsal and ventral margins, numerous yolk-gland follicles 

 will be seen. Those at the ventral edge approach nearer to the middle 

 line than those of the dorsal edge ; they do not, however, touch it. 

 On the dorsal side, the space between the yolk-gland follicles and 

 the middle line is occupied by the larger branches of the testes, which 

 also extend into the central field. A transverse section taken at the 

 level of the ovary will show parts of this organ upon one side ; 

 towards the centre, the uterus folds containing eggs will be seen, in 

 section. If the eggs have taken the stain well, the details of their 

 structure namely, the lidded shell, germ-cell, and numerous yolk- 

 cells will be apparent. In sections taken a little lower down, the 

 shell-gland will also be seen. Longitudinal sections through the head 



