83] UFE HISTORY OF TREMA TODES—FA UST 83 



place in the cercariae of this species. The median tail tube receives six lateral 

 tributaries, the anteriormost of which is reflexed. The rami have each 

 an unbranched tubule. 



The cephalic region is marked by a large invertible sucker, extending 

 thru the anterior third of the body. No intestinal ceca whatever have been 

 observed in this species. No glands surround the esophagus as a distinct 

 ring, altho the entire esophageal tube lining is glandular in nature. Four 

 small salivary-mucin glands are situated in the posterior third of the body 

 (Fig. 155). Their thick ducts empty into the oral cavity as heavy 

 bundles. The cells of this system are filled with closely aggregated, deeply 

 staining granules. The nucleus of the salivary-mucin gland cell is extremely 

 small. 



This species possesses neither pigment eye nor eye-spot without pigment. 



Encystment has not been observed in this species. 



Cercaria tuberistoma is probably a schistosomatid larva. 



