Dr. O^Bryen Bellingham on Irish Entozoa. 439 



29. Distoma. . Intestine of holibut (Hippoglossus vulgaris). 



30. *. Intestine of sun-fish (Orthagoriscus Mola). 



[31. t- CEsophagus of common snake (Natrix torqmta).] 



than twice the size of the ventral ; ventral pore distant, seated near 

 the centre of the body. 



* This species of Distoma, which I found in the intestines of the 

 sun-fish (Orthagoriscus Mola), has not been previously described. It 

 belongs to the division in which the body is cylindrical, and to the 

 subdivision in which the pores are of unequal size. It measures from 

 4 to 5 lines in length ; colour a dirty yellow after remaining in spirits 

 of wine ; body cyUndrical ; greatest diameter near the ventral pore, 

 diminisliing gradually towards each extremity ; neck cylindrical ; 

 both pores elliptical ; the long diameter of the anterior transverse, of 

 the ventral pore longitudinal ; ventral pore larger than the anterior, 

 and prominent. 



This species of Distoma differs from the D. contortum (which in- 

 habits the gills of the sun-fish) in being of a different colour and 

 smaller size ; the ventral pore is not pedunculated as it is in the D. 

 contortum and D. nigroflavum ; the body of the animal does not be- 

 come curved after being placed in spirits of wine, and the head or 

 neck is not armed with spines, in which it also differs from those 

 two species. 



t I have found many specimens of an undescribed species of Di- 

 stoma in the oesophagus of the common snake (Natrix torquata), which 

 is an inhabitant of England, but not of this country. This species is 

 more tenacious of life than most other Distomata, as it lived for some 

 time in a vessel of fresh water. It belongs to the division in which 

 the body is cyhndrical, and to the subdivision in which the pores are 

 of equal size. It measures a line and a half in length when fully 

 extended, when contracted about a line. The body is cylindrical, but 

 when the animal is fully extended, it appears to be flattened, although, 

 after it has been kept in spirits of wine for a short time, it becomes 

 cylindrical. The colour of the body between the anterior and ventral 

 pore is white, and two vessels are seen here passing backwards from 

 the anterior pore ; the ovaries, which occupy the sides of the body, 

 are of a reddish colour ; posteriorly the body is filled with a black 

 substance, similar to what is seen in the D. cylindraceum, from which 

 circumstance the species might perhaps be named Distoma nigro- 

 venosum ; the greatest diameter of the body is about the ventral pore ; 

 the caudal extremity is obtuse. When the animal is alive, the an- 

 terior pore is sometimes larger, sometimes smaller than the ventral ; 

 its shape is also either orbicidar or elliptical ; after its death, both 

 pores become orbicular and of equal size ; the ventral pore is promi- 

 nent. The distance between the pores also varies during the motions 

 of the animal; after it has lain in spirits of wine, they are seated close 

 to one another. 



