TREMATODES OF AUSTRALIAN BIRDS. 189 



living state and after preservation, the body in all cases 

 was bent in the form of a narrow V» the anterior half 

 bending down sharply, in a ventral direction on to the 

 posterior half. When this was pushed back, the worm 

 showed the very characteristic T shape, with the thin, 

 expanded anterior end, produced outwards into a pair of 

 lateral wings. The worms were quite flat, i.e., their dorso- 

 ventral thickness was quite small in comparison with their 

 width. The Australian form proved to be shorter and 

 broader than the African. The length varied from 3 to 

 3*25 mm., the breadth of the anterior part being 2*2 mm., 

 that of the posterior part 1*17 mm. The cuticle is smooth, 

 but sections showed the presence of small spines lying in 

 the cuticle, hardly projecting on the surface : the striping 

 of the anterior end mentioned by Jagerskiold, and pro- 

 duced by the presence of numerous longitudinal grooves on 

 the surface, was hardly noticeable. The suckers are small* 

 but larger than those of its congener, though the latter 

 worm is larger. The oral sucker is 0*134 X 0*107 mm.; 

 the pharynx is 0*096 x 0*075 mm., the combined ventral 

 and genital sucker 0*276 X 0*214 mm. 



The excretory pore is situated on the dorsal aspect of 

 the body 0*07 -0*13 mm., from the posterior end. 



Alimentary Canal, — The pharynx is fairly well developed, 

 the oesophagus narrow and moderately long (0*27 mm.), the 

 intestinal limbs reaching almost to the posterior end of the 

 body, and following the contour of the lateral borders, so 

 that in the anterior part of the body they form wide bays 

 extending into the lateral wings of the worm. The intes- 

 tinal limbs, while being comparatively narrow, (0*05 mm.) 

 in diameter, are much wider than in S. expansus, where 

 they measure only 0*012 mm. 



Excretory System, — The excretory vesicle, while con- 

 forming, in general, pretty closely to the form described 



