TREMATODES OP AUSTRALIAN BIRDS. 241 



Cycloccelum taxorchis differs from all the other species 

 of the genus in the arrangement of the testes side by side 

 on either side of the middle line. From each of the species 

 separately it shows a number of characteristic differences, 

 and appears to be most closely related to C. brasilianum^ 2 ^ 

 which is parasitic in the South American bird Totanus 

 flavipes, a bird closely related to Limosa novce-hollandice y 

 the host of the Australian fluke under consideration. The 

 latter resembles Cycloccelum brasilianum, and differs from 

 the other species in its small pharynx and long oesophagus 

 and in the forward extension of its yolk gland fields. 



It differs from it, however, in the cirrus sac reaching the 

 intestine, which it always fails to do in 0. brasilianum; in 

 the testes being equal in size while they are unequal in the 

 Brazilian form and in the very characteristic arrangement 

 of the testes. 



H.EMATOTREPHUS ADELPHUS, Sp. n. (Fig. 24.) 



Diagnosis. — Moderate sized worms, 8-14 mm. long, 

 pointed at the anterior end, rounded at the posterior, with 

 the maximum breadth near the posterior end. Mouth 

 cavity crescentic in transverse section. (Esophagus want- 

 ing. Intestinal limbs half ivay between middle line and 

 lateral edge of the body. Genital pore at the posterior 

 end of the pharynx. Cirrus sac projecting a little behind 

 the intestinal fork. Yolk glands confined to the lateral 

 fields, but meeting in the posterior end of the body. Mature 

 eggs very large, 0*24 x 0*107 mm. 



Host. — Himantopus leucocephalus, in the body cavity. 



Type specimen in the Australian Museum, Sydney, No. 

 W. 445. 



Twelve specimens of this species were obtained from the 

 body cavity of the White-headed Stilt, Himantopus leuco- 

 cephalusy in South Australia, by Dr. J. Burton Cleland of 



P— December 6, 1916. 



