TRBMATODE PARASITES. 57 



food. It is, however, useless to speculate on these matters, and 

 for the present we are content to record the negative result of 

 this particular experiment. 



Our main object in submitting the present communication is to 

 give an account of the new species of Gymnophallus which were 

 encountered in the course of examining the Scoters, and also 

 to note the occurrence of a few other Trematode parasites which 

 have hitherto not been recorded from this host. Nicoll(1907) 

 gives the following list of Trematode parasites from CEdemia 

 nigra examined at St. Andrews : — 



Gymnophallus cUqjsilis Nicoll. Bursa Fabricii. 



Psilostomum hrevicolle Creplin. Intestine. 



Spelotr&ma pygmceum Levinsen. Intestine. 



The following have been recorded by other authors : — 



Psilochasmus oxyurus Creplin. Intestine. 



Echinostomiim revolutum Froelich. Intestine. 



Monostomum sp. Respiratory tract. 



Strigea tarda Steenstrup. Intestine. 



In the course of our examination we found the following : — 



Psilostomum hrevicolle Creplin. Intestine. 



Tocotrema concavum Creplin. Intestine. 



Levinseniella hrachysom.a Creplin. Intestine. 



Metorchis xanthosomus Creplin. Gall-bladder. 



Gymnophallus dajysilis Nicoll. Intestine. 



Gymnophallus hursicola Odhner Bursa Fabricii. 



Gymnophallus oedemia;, sp. n. Intestine. 



Gym,nophalhos affinis, sp. n. Intestine. 

 Gymnophallus macroporus, hom. nov. Intestine. 



Gymnophallus ovoplemis^ sp. n. Intestine. 



Catatropis verrttcosa Froelich. Bursa Fabricii. 



This makes a total of 15 distinct species from this single 

 host, of which 9 are here recorded for the first time. Such a 

 wealth of varieties of Ti'ematode parasites in a single host is 

 rather remarkable *. 



The new species which we are describing were all obtained from 

 the Scoters supplied by the Brighton Aquarium. The birds 

 originally came from the same quarter as those purchased through 

 the Zoological Society, and it is rather striking that they should 

 have been so heavily infected, while the othei's were almost free 

 from Trematodes. 



Gymnophallus cedemi^, nom. nov. 



= Lecithodendrium somaterice. Jameson, 1902 (ex parte). 



This was the least common of the four species, and occurred in 



* [To the list must be added Paramonostomiim alveatum Melilis, wliich was 

 obtained from a Scoter {(Edemux nigra.) which died in the Society's Gardens on 

 Xov. 19th. ]911.-^W.N. : . - . 



