Dr. O'Bryen Bellingham on Irish Entozoa. 339 



o . ,. ^ . ^ 4- r Small intestine of wild duck (Anas 



o. Amphistoma isostomum^ < li j, \ 



4 7 + / Small intestine of northern diver (^Co- 



" ^ ■ " ' y hjmbus glackdis). 



r •, X f Small intestine of heron {Ardea citie- 



o. cornu : I . . . . < . 



[ rea). 



o . ; e f Small intestine of rook (CorvMs/rwoj- 



b. spheerula *j . . s / \ 



^ I legus). 



Species dubice. 



rSmall intestine of sparrow-hawk {Ac- 



f, 4 1- . „ j ciniter frinqillarius) . 



7. AmphistomaW < o ii • :. ^- r u j /o 



' " j Small intestine or moor-buzzard {Bu- 



y_ teo rufus). 



* The Amphistoma isostomum has a general resemblance to the 

 A. macrocephalum ; it is however much smaller. My specimens are 

 about half a line in length : the animal appears to be divided into 

 two equal parts by a simj:)le fissure extending round it ; the anterior 

 is regarded as the head, the posterior as the body ; the former has a 

 white colour, the latter is yellow. 



t The Amphisto7na gracile is rather a rare species ; Bremser dis- 

 covered it in the Mergus Merganser. I found it in the small intestine 

 of the Colymbus Immer (young of Colymbus glacialis). It is about two 

 lines and a half in length ; colour white. The head is distinct from 

 the body, nearly of the same diameter as it, and about a third of its 

 length. The body of the recent animal is cylindrical ; it becomes flat- 

 tened in spirits of wine, and sometimes concave on the abdominal, 

 and convex on the dorsal surface. The anterior pore is large and cup- 

 shaped ; after it has lain in spirits it presents a lobated appearance : 

 the posterior pore is somewhat triangular, not quite terminal, more 

 upon the inferior surface of the caudal extremity ; it becomes orbi- 

 cular and terminal when kept in spirits of wine. 



+ I have only once met with this species ; the specimens which I 

 possess are very minute, and have some of the characters of the 

 Monostoma cornu, with which Rudolphi says it may be readily con- 

 founded. 



§ The Amphistoma spheerula, from the small intestine of the rook 

 (^Corvus frugilegus), is scarcely a line in length, and of a dirty yellow 

 colour ; the head and body are distinct, but this is not so well marked 

 as in other species; the body is cylindrical, about twice the length 

 of the head. The anterior pore is lobed, the posterior orbicular and 

 smaller. 



II This species of Ainphistoma, which I found in the small intes- 

 tine of the sparrow-hawk and moor- buzzard, has some resemblance 

 to the Atnphistoma pileattim oi Rudolphi's ' Synopsis ;' from which it 

 differs in the terminal pore being larger than the anterior, and in the 

 body being shorter and thicker. 



12 



