299 



about the length of the preceding one, and widening somewhat distally, with the 

 lateral corners conically produced, anal opercle smooth. Caudal rami of a some- 

 what unusual shape, being sub-lamellar and, as it were, distorted, with the inner 

 edge boldly curved, and the tip pointing obliquely outwards, lateral setae closely 

 juxtaposed and rather small, dorsal seta issuing from behind the middle, apical 

 setse short. Anterior antenna? not very strong, and scarcely more than half as 

 long as the cephalic segment, 3rd joint about the length of the 2nd, terminal part 

 half as long as the proximal one. Posterior antennae with the terminal joint 

 shorter than the basal one, and widening considerably distally, outer rarnus small, 

 but well defined. Mandibular palp with 2 small lateral lobules, each tipped with 

 a short ciliated seta, the tip itself carrying 2 somewhat larger setae. Posterior 

 maxillipeds not very strong, hand oblong oval in form and finely ciliated inside, 

 dactylus very thin, with a slender bristle issuing from the base outside. Natatory 

 legs with the rami somewhat robust, the inner one in the 3 anterior pairs being 

 about 2 /3 as long as the outer, in the 4th pair considerably shorter. Last pair 

 of legs with the distal joint rather large,- oblong in form, and clothed on the outer 

 edge with a very dense fringe of stiff hairs, marginal setae 4 in number and rather 

 strong, spiniform, 3 of them issuing from the transversely truncated end, the 4th 

 at some distance from the tip outside; inner expansion of proximal joint conically 

 produced, and extending to the middle of the distal joint, carrying 3 spiniform 

 setae, one at the tip, the other 2 at the inner edge, near the base. 



Male of about same size as female, and having the caudal rami of a 

 somewhat different shape, being narrower and less distorted. Anterior antennae 

 very strongly built, 7-articulate, with the 4th joint greatly dilated at the base, 

 terminal part slender, 3-articulate. Inner rarnus of 3rd pair of legs with the 

 apical spine much coarser than in female, and not defined at the base. Last pair 

 of legs scarcely smaller than in female, but differing somewhat in the shape of 

 the inner expansion of the proximal joint, and in the absence of one of the spines 

 on the distal joint. 



Colour dark yellowish brown. 

 Length of adult female 0.62 mm. 



Remarks. This form, as stated above, ought to be considered as the type 

 of the present genus. It is easily distinguished from the other 2 species here 

 recorded by its more robust body and by the peculiar shape of the rostral pro- 

 jection and of the caudal rami. The densely hairy clothing of the distal joint of 

 the last pair of legs is another character by which the present species is distin- 

 guished, and which has given rise to the specific name hirsutipes given to this 

 form by Th. Scott. In the living state it is also at once recognised by its yel- 



