BY S. J. JOHNSTON. 329 



Eggs. — The oldest eggs in the uterus, situated in the coils 

 just behind the ventral sucker, and in the loop passing for- 

 wards to the genital opening, with perfectly smooth and un- 

 wrinkled surface and full contents, show no sign of shrink- 

 age, and measure 0-033 >^ 0-0214 mm. 



Gorgodera australiensis is found in the bladder of Hyla 

 aurea and of Limnodynastes peromi. It is rather commoner 

 in the Hyla, 75 of my mounted specimens coming from that 

 frog, as against 23 from Limnodynastes. Sometimes only 

 two or three worms will be found in the same bladder, but 

 more generally one finds ten or a dozen. 



The Australian species differs from the European G. cyg- 

 noides in its smaller size, and in the relatively smaller size 

 of the ventral sucker, in the shape of the ovary and its posi- 

 tion in regard to the testes, and in the length of the united 

 portion of the vas deferens, as well as in the size of the eggs. 

 It further differs from the American species, G. ampUcava, in 

 size (the largest G. amplicava being smaller than the average 

 Australian form), and in the proportional size of the suckers. 

 The ratios of oral to ventral sucker in G. australiensis, G. cyg- 

 noides, and G. ainplicava are respectively, 2:3, 2:4, 2:5 

 (Stafford, 89), or 2 : 6 (Bensley, 3). 



Ssinitzin's paper on the trematodes of frogs near Warsaw 

 (84), in which he makes four species of European trematodes 

 belonging to the genus Gorgodera, I have unfortunately not 

 been able to see. 



Literature -3, 8, 42, 48, 50, 52, 59, 67, 68, 71, 72, 84, 89. 



Genus Mesoccelium Odhnr. 



Subfamily Brachycoeliinas Loose. 



(Figures 13, 14, 15, 69-76.) 



Diagnosis. — Small, somewhat oval flukes, more or less spiny, 

 oral sucker the larger, with pharynx, moderately long oesopha- 

 gus, and short intestinal limbs reaching to, or a little beyond, 

 the middle of the body. Excretory vesicle tubular and long. 



