106 

 I. Sphaeronella elegantula n. sp. 



(PL II, fig. 2.a-2g.) 



FEMALE. An adult specimen (fig. 2a) was L31 mm. long and 1-16 mm. broad; 

 the head is a little more than middle-sized, the trunk globular. One of the specimens 

 dissected differed considerably in hair-covering from the two others and may be described 

 first. Tufts or rows of hairs were found on the proximal part of the inner side of the basal 

 joint of the maxillae and on the skeleton in front of and outside the articulation of the maxillae, 

 in front of the anterior inner angle of the maxillipeds, above their posterior inner angle and 

 behind their articulation. The greater part of the trunk was naked; a moderately broad, 

 transverse belt behind the head was rather closely covered with most peculiar hairs, which 

 are also found on the genital area. This area (fig. 2 e) is considerably broader than long, 

 and the solid chitine forms a rather broad ring and a median list which is broad posteriorly; 

 the distance between the genital apertures is of medium length ; the caudal stylets are situated 

 far from each other and at a considerable (though not equally considerable) distance from 

 the posterior margin of the area. The region between the caudal stylets, the interval between 

 these stylets and the genital area, the posterior part of the genital area, the part in front 

 of it and just inside its outline are more or less densely covered with most peculiar, very 

 broad, somewhat flattened, long hairs, which, however, are so strangely transparent and 

 membranous, that their outlines are difficult to follow, whereas, on the contrary, their bases 

 form conspicuous ovals, one half of which is more distinct than the other (in fig. 2 e all these 

 ovals are drawn, but only very few of the hairs themselves). — In another specimen the 

 ventral side of the head had hairs only in front of the basis of the maxillae and at the 

 anterior and posterior inner angles of the articulation of the maxillipeds. Behind the head 

 the trunk had a belt provided with short and fine, basally somewhat dilated hairs. The 

 genital area had nearly the same shape as that of the preceding specimen, but its posterior 

 margin was slightly more concave; the caudal stylets were situated a little nearer (but not 

 equally near to) the area, and the part between and behind the genital apertures, as well 

 as the skin stretching from the genital area to a good distance behind the caudal stylets was 

 less densely furnished with hairs of the same shape as those on the front part of the trunk, 

 while the membranous hairs were entirely wanting. — A third specimen agreed essentially 

 with the last-mentioned one. 



MALE. The largest specimen is -31 mm. in length, the smallest, which is not full- 

 grown, measures '23 mm. It is of medium size compared with the female (fig. 2 b : 

 fig. 2 a). The body comparatively slender (fig. 2f). The lateral margins of the median 

 frontal plate diverge distally, the anterior angles are sharp. The processes between the base 

 of the maxillipeds are long or very long; the trunk-legs proportionally long; the terminal 

 seta of the branch on the first pair and of the inner branch in the second pah' longer 

 than the leg-. 



