BUCCINTJM. 359 



PARASITES. 



Two extremely interesting parasites have been found 

 in the whelks from Port Erin. One of these is a 

 Coccidian (Merocystis hathae, Dakin), and the other is an 

 endoparasitic Turbellarian first found 14 years ago by 

 Jameson, and re-discovered this year in whelks from the 

 same district. The Turbellarian [Graffilla buccinicola) 

 belongs to a genus of parasitic rhabdocoeles which occurs 

 frequently in mollusca, but at the time of Jameson's 

 discovery Graffilla had not been found in British waters. 

 No further details of its anatomy will be given here, 

 because it seems advisable that the species should 

 undergo a thorough re-examination. One point, however, 

 must be referred to. Jameson states that the parasite 

 occurs in the kidney and ' i kidney duct ' ' of Buccinum 

 undatuin and Fusus antiquus, and that almost all whelks 

 examined were infected. My specimens were examined 

 fresh, and considerable numbers were investigated. In 

 all cases the parasites were found in the stomach and 

 rectum, and there were as many as 14 seen in the stomach 

 of one individual. 



It is somewhat difficult to conjecture what the 

 " kidney duct " referred to in Jameson's description can 

 be, for the renal organ opens directly at one end into the 

 mantle cavity. The minute reno-pericardial canal can 

 hardly be called a kidney duct ! 



