BY S. J. JOHNSTON. 327 



sucker; diameter 2*5 mm. Both suckers very muscular, devoid 

 of hooks or lobes of any kind. 



Common genital aperture situated near the middle line about 

 half-way between the oral and ventral suckers. Excretory aper- 

 ture situated at the extreme posterior end. Laurer's canal 

 opening on the dorsal surface about the middle of the body. 



Cuticle with a transversely striated appearance owing to fine 

 closely arranged grooves running round the worm. 



Alimentary canal simple; mouth situated at the base of the 

 oral sucker, leading into a well developed, muscular pharynx; 

 behind the pharynx the canal immediately divides into the two 

 limbs of the intestine, the oesophagus being practically non- 

 existent. Limbs of the intestine unbranched, but not quite 

 simple, being thrown into bays and folds throughout their length; 

 they terminate in blind sac-like ends at the posterior end of the 

 body. Walls of the intestine thick, lined by long columnar cells, 

 nucleated at the base, of a glandular character. 



Excretory system very well developed, consisting of two main 

 canals which run forwards and unite in front of the oral sucker. 

 In the anterior half of the body these excretory vessels run 

 laterally; but some distance behind the testes they bend inwards 

 and meet about the middle line to form a single median vessel, 

 which opens into a large excretor}^ vesicle in the posterior end of 

 the body. A number of constrictions occur along the excretory 

 canals. The excretory vesicle opens on the exterior through a 

 very short canal, ending in the excretory pore. The excretory 

 canals were partly filled up with crystals belonging to the cubical 

 system, and which had become stained by eosin; some envelope 

 crystals of calcium oxalate were present. 



Testes two, situated just posterior to the middle of the bod}-, 

 ovoid in shape; lying almost on the same level. The undeveloped 

 sperms give their interior that follicular appearance usual in 

 Trematodes, but there is also a large number of fully developed 

 sperms present. Each vas deferens, passing dorsal to the uterus 

 and ventral sucker, joins its fellow at the origin of the vesicula 

 seminalis, which is large and pear-shaped, and filled with fully 



