92 Wr. H. A. Baylis on a 



owiiio- to tlie manner in wliicb they are obscured by tbe other 

 or<Taus. Tlie diagram (fig. 2) shows in a schematic manner 

 their probable relation to each other and to the dorsal sac, 

 I'he proximal end of each tube appears to open into a small, 

 elongate, bladder-like organ, which communicates "with the 

 diverticulum of the sac. Each tube runs forward to about 

 the level of the hinder end of the pharynx, then doubles 

 immediately backwards to run down the side of the body with 

 a sinuous course, giving off frequent fine branches which end 

 in tiame-ceils scattered among the parenchyme. The tubes 

 are finally lost among the vitelline glands on either side. 

 The "bladder" and collecting vessel of the left side lie 

 dorsally to the cirrus-sac, vagina, and intestinal csecum, 

 "while the apparatus of the right side appears to pass ven- 

 trally below these structures. 



Note on the Affinities of the Species. 



On a general consideration of its structural characters this 

 form seems to approach most closely to the Trematodes of 

 the family Le{)odermatidse. Among the important features 

 of this family (Odhner, 1911, p. 22) are the following: — 



The skin is armed with scales or spines, which generally 

 occur all over tlie body. The oral and ventral suckers are 

 moderately close together. The alimentary canal consists of 

 prepharynx, pharynx, oesophagus, and two simple intestinal 

 branches. The excretory vesicle is Y-shaped, the division 

 into the two arms of the Y occurring just behind the shell- 

 gland and associated organs. The genital pore is situated 

 typically at a short distance in front of the ventral sucker, 

 but more or less to the left of the middle line. [In Renifer 

 and Ochetosoma this displacement is very marked, and the 

 pore is nearly at the edge of the body; it is also situated far 

 to the left in Lechriorchis.^ The cirrus-sac is usually curved 

 in a crescentic manner from its opening to its inner end, is 

 provided with conspicuous longitudinal muscles, and has an 

 internal seminal vesicle, a pars prostatica, and an eversible 

 cirrus. The ovary is on the right side, behind the ventral 

 sucker. The left testis is usually somew^hat in front of the 

 right. A receptaculum seminis may or may not be present. 

 The vitelline glands are at the sides of the body in the middle 

 region. The eggs are from 0'02 to 0'05 mm. in length. 



In almost all the particulars enumerated above'tlie present 

 species agrees, as will be seen from the foregoing description. 

 The only points in which it is exceptional are the unequal 

 size of the testes and the condition of the excretory system. 



