302 ON SOME TREMATODE PARASITBS OF AUSTRALIAN FROGS, 



Farailv PARAMPHiSTOMiDif: Fischdr. 

 vSubfamily Cladorchinae Fischdr. (?). 

 DiPLODISCUS MEGALOCHRUS,* Sp.n. 



(Figures 29, 31-42.) 



Diagnosis. — Subclavate worms, 3-4 mm. long, by 1-25 to 

 1-5 mm. broad. Integument smooth. Suckers comparatively 

 large; ratio of (Ulterior sucker to posterior, 3 : 10. Diverticula 

 of. the oral sucker well developed; oesophagus long, pharynx 

 well-developed, at the posterior end of the oesophagus. Intes- 

 inal limbs moderately wide and short. Excretory pore at the 

 extreme posterior end of tlie body. Genital opening behind 

 the intestinal fork. The single testis large and generally 

 somewhat cubical ; a large vesicula seminalis arranged in a 

 number of coils. Copulatory organs present. (J vary oval, 

 behind the testis ; shell-gland about as large as the ovary. 

 Vitelline glands of large follicles, partly in a single, and 

 partly in a double row along the sides of the body, outside 

 the intestinal limbs. Coils of the uterus occupying a great 

 part of the body-space, from the posterior end to the genital 

 opening. Eggs with thin, hyaline shell, 0-132 x 0*066 mm. 



In the rectum of Hyla aurea and L'lninodynastes peronii. 



Type-specimen in the Australian Museum, No. W.332. 



This species of Diplodiscus occurs in the rectum of Hyla 

 aurea and Limnodynastes peronii. I have obtained 19 speci- 

 mens from the former, and 10 from the latter, 15 in all being 

 sectioned. 



The worm is .somewhat club-shaped widfr a little in front 

 of the posterior sucker, very bhintly rounded behind : in front 

 tapering to a much smaller diameter. Except near tlie anterior 

 end, where it is fairly circular, the cross-section of the body is 

 elliptical, but somewhat flattened dorso-ventrally. The aver- 

 age length is 3-72 mm., breadth 1-37 mm. 



* jXiyas, large; "'X/"'^' yolU, referring to the large yolk -follicles. 



