1913.7 T. South VVEI.1:, : Parasifes from Fish. 91 



thickness was approximately i mm. This larva is very widely 

 distributed in the coelom of fishes^ particularly Cyprinoids. It 

 becomes adult in from one to two days in the intestine of certain 

 water birds, such as those of the genus Sterna, Lams, Colymbus, 

 Urinator, etc.. which normally devour infected fishes. The adult 

 worm {Ligula intestinalis, Linnaeus) sometimes measures i metre 

 long and from 5-15 mm. broad, and differs but little from the 

 larval form. 



In the Indian Museum there are the following specimens of 

 this larva : — 



I. One specimen from Laheo roJiita (Bengali, Rohii), measur- 

 ing 165 mm. long and 10 mm. broad. 



II. One specimen from Nemachilus rupicola (Bengali, Korika), 

 length 69 mm., breadth 5"5 mm., from a small mountain stream 

 in the East Himalayas. 



III. Three specimens with no histor}' having the following 

 measurements : — 



{a) Length 147 mm. Breadth 9 mm. 



{h) ,, 165 mm. ,, 10 mm. 



(c) (Fragmented). Over 350 mm. long and 9 mm. broad. 



The parasite is strap-shaped, and in our specimens the 

 extremities vary considerably in appearance. In three specimens 

 both the anterior and posterior extremities are deeply concave. 

 In the remaining two, the posterior extremit}" tapers gradually to 

 a rounded point, whilst the anterior extremity is broadly rounded 

 with deep, acute, median indentation. The structure and anatomy 

 of Ligula catastonia is described b}" Linton. 



These larval Cestodes form articles of food in Italy where 

 the}' are sold in the markets as " Maccaroni piatti," and in southern 

 France where they are sold in the markets as " Ver blanc " and 

 eaten extensively. 



Trematoda. 



Isoparorchis, gen. nov. 



Leaf-like and translucent worms, longer than broad. Oral 

 and ventral suckers present, the latter being near the anterior ex- 

 tremity. Genital aperture almost midway between the two suckers. 

 Each intestinal ramus in the form of a continuous letter S extend- 

 ing to the posterior margin of the worm. Testes in front of ger- 

 marium, paired and globular, anterior, one on each side and very 

 slightly posterior to ventral sucker. Vitelline glands dendritic and 

 posterior. Germarium single, tubular and posterior. Uterus single, 

 very long, disposed along the laterally directed loops of each ramus 

 of the intestines, passing from one loop on one side to a loop on 

 the other side alternately, across the body of the worm, to a point 

 near the ventral sucker. It then runs straight in the median line 

 to the genital aperture. Shell gland minute, situated at the junc- 

 tion of the uterus with the duct of the vitelline glands. Excretory 

 pore terminal, median and posterior. Vesicle of varying size. 



