TREMA.TODES OF AUSTRALIAN BIRDS. 195 



the testes they extend inwards towards the middle line. 

 This disposition corresponds pretty closely with what 

 occurs in S. expansus. 



The eggs are a broad oval, the average size of all those 

 measured (a large number) being 0*029 X 0*02 mm. The 

 smallest egg measured was 0*024 x 0*019 mm., the largest 

 0*032 X 0*022 mm. They are thus distinctly larger, and 

 -especially broader than those of S. expansus, which measure 

 •0*027 X 0*016 mm. 



The chief differences between S. expansus and S. australis 

 are that the latter is shorter and broader, but at the same 

 time has somewhat larger suckers and pharnyx; the testes 

 are very deeply lobed in S. expansus, but solid bodies with 

 their surfaces marked rather into low ridges by shallow 

 .grooves in S. australis; and the eggs are larger, especially 

 •broader, in the latter. 



Subfamily ECHINOSTOMINiE. 

 HlMASTHLA HARRISONI, Sp. n. (Fig. 10.) 



Diagnosis, — Elongated, attenuated worm, flattened dorso- 

 ^ventraliy. Integument closely beset with thick spines. 

 Head-collar with twenty-four spines in a single row on its 

 border. Ratio of oral to ventral sucker 1 : 4. Testes and 

 ovary close together in the posterior fifth of the body length. 

 Yolk-glands confined to the posterior half of the body. 

 Eggs broad elliptical, but pointed at both ends, 0*091 X 

 0*069 - 0*096 x 0*074 mm. 



Host — Numenius cyanopus, in the intestine. 



Type specimen in the Australian Museum, Sydney, 



No. W, 427. 



Three specimens of this worm were obtained from the 

 Curlew, Numenius cyanopus, at Masthead Island, off the 

 Queensland Coast, and one at Gladstone Q., by Launcelot 

 Harrison, demonstrator of Zoology in Sydney University. 



