56 



somewhat in length the anal segment, and obpyriform in outline, being rather 

 broad at the base and gradually tapered distally, inner edge considerably 

 bulged at the base and, like the outer, coarsely ciliated; seta of outer edge 

 attached far in front; dorsal seta well developed and issuing a little farther 

 behind; apex provided with only a single well-developed seta flanked by 2 

 small bristles. Anterior antennae a little shorter than the cephalic segment, 

 with the joints rather sharply marked off from each other, terminal part a 

 little shorter than -the proximal one. Posterior antennae with the outer ramus 

 comparatively small, though distinctly biarticulate, distal joint short, carrying 

 on the tip a stout spine and a short seta. Mandibles with the palp very small, 

 uniarticulate, with 2 apical setae. Maxillae and maxillipeds of normal structure. 

 1st pair of legs with the inner ramus considerably longer than the outer, though 

 only composed of 2 joints; middle joint of outer ramus wanting the usual 

 seta inside. The 3 succeeding pairs of legs having the outer ramus rather 

 strongly built, with the spines very coarse; inner ramus, as usual, poorly 

 developed, biarticulate, with the distal joint very narrow and only carrying a 

 single apical seta. Last pair of legs of moderate size, with the distal joint 

 oval in form and edged with 5 setae, the middle one small and not ciliated; 

 inner expansion of proximal joint narrow linguiform and not extending as far 

 as the distal joint, marginal setae 5 in number. 



Male smaller than female and exhibiting the usual sexual differences, 

 being moreover distinguished by the much smaller size of the caudal ranii. 

 Inner ramus of 2nd pair of legs comparatively larger than in female, extending 

 about to the middle of the terminal joint of the outer; that of 3rd pair trans- 

 formed in the usual manner, being distinctly 3-articulate, with the middle joint 

 produced at the end outside to a strong mucroniform process. 4th pair of 

 legs with the spine attached to the middle joint of the outer ramus very strong 

 and somewhat twisted; inner ramus very small and tipped with a strong 

 spiniform seta and a much smaller bristle. Last pair of legs, as' usual, much 

 reduced in size. 



Colour witish gray, with a faint yellow tinge. 



Length of adult female 0.63 mm. 



Remarks. This form, first described by Mrazek as a species of Can- 

 thocamptus, ought evidently to be referred to the present genus, as defined in 

 Vol. V. It is easily recognised by the comparatively large size of the caudal 

 rami, which however, unlike what is generally the case, exhibit a somewhat 

 different appearance in the two sexes. 



