222 S. J. JOHNSTON. 



and behind it lie the prepharynx and oesophagus respec- 

 tively, exactly equal and conspicuous for their length, 

 varying in different specimens from 0*079 to 0*107 in length. 

 The intestinal limbs are wide and without caeca, but pursue 

 &, wavy course, gradually diverging from the middle line to 

 the level of the ventral sucker. 



Branched excretory vessels run back along the sides of 

 the body to join the V-shaped excretory vesicle. The 

 genital pore is situated on the left side of the ventral sucker, 

 about its middle. There is a voluminous cirrus-sac and 

 pars prostatica, and the copulatory bursa is rather smaller 

 than in the other species of this genus. The gonads are all 

 oval and have their long axes placed transversely, the ovary 

 on a level with the ventral sucker and to its right; the testes 

 symmetrically one on either side of the middle line. The 

 testes are equal in size, 0*107 x 0*08 mm.; the ovary is 

 smaller, 0*08 x 0*053 mm. 



The yolk glands are arranged in three main groups of 

 follicles on each side, and in whole mounts are a good deal 

 concealed by coils of the uterus, which forms a number of 

 loops in the posterior part of the body behind the testes. 

 The eggs are very small and oval, varying from 0*017 x 

 0*0138 up to 0*018 x 0*0138 mm. 



This pretty little worm seems to be most closely related 

 to Jagerskiold's L. brachysoma^ parasitic in the caecum of 

 a bird of the same genus in Scandinavia, namely Charadrius 

 Maticula. It differs from this species, however, in its more 

 elongated and slender form; and in the ratio of the suckers 

 to one another. In the present species they are exactly 

 equal, while in L. brachysoma, Jag. the oral is twenty per 

 cent, larger than the ventral. (15 > p - 14 °) The pharynx is smaller 

 in L. howensis and the limbs of the intestine are without 

 oaeca. While on the whole, the arrangement and structure 

 ■of the genital organs are pretty much the same in these 



