Plate XX. 



Teistomum sinuatum. 



Fig. 1. The whole worm viewed from the ventral side. The vitellarium is re- 

 presented only on one side, and tlie nervous and excretory systems on the 

 other. Nervous system sliaded with parallel lines; excretory system 

 shaded darkest. 



„ 2. One of the hooks of the posterior sucker, x 204 diam. 



„ 3. Chitinous corpuscle at the opening of the lateral gland, x 204 diam. 



„ 4. Three elevations of the posterior sucker at the point of their junction, 

 in a surface view, x 204 diam. 



„ 5. Cross-section of the posterior sucker through its stalk, x 29 diam. 



„ 6. A small portion of the radial section of the posterior sucker transversely 

 to the long axis of the hody. x 204 diam . 



„ 7. A small portion of the tangential section of the posterior sucker, x 73 

 diam. 



„ 8. A portion of the cross-section of the body at the level of the oesophagus, to 

 show the salivary glands, x 73 diam. 



„ 9. Two cells of the salivaiy gland, x 427 diam. 



„ 10. A portion of the cross-section of the anterior sucker of the right side aud of 

 the adjoining part of the body, x 204 diam. 



