72 GL O. Sars. 



Description of the female. 



The length of fully adult, ovigerous specimens does 

 not exceed 1.28 mm., and this form accordingly is very 

 inferior in size to any of the other known species. 



The body is, on the whole, much more slender than in 

 the preceding species, and in this respect also surpasses 

 the New Zealand form. The anterior division exhibits, when 

 seen dorsally (fig. 5), a very narrow oblong, almost cylindrical 

 form, the greatest width scarcely exceeding 1 /3 of the length. 

 Anteriorly it somewhat tapers towards the obtusely rounded 

 front, whereas posteriorly it is scarcely at all narrowed. The 

 lateral expansions of the last segment are not nearly so 

 fully developed as in the 3 other species, and extend but 

 little beyond the middle of the 1st caudal segment. They 

 are each divided into 2 well-defined lobes, the outer of 

 which is the larger, and of a short lanceolate form, whereas 

 the inner is more triangular in shape. 



The tail does not attain half the length of the anterior 

 division, and has the caudal rami somewhat smaller than in 

 B. robusta, not nearly attaining the length of the 2 pre- 

 ceding segments combined. 



The eye is very conspicuous, the pigment being of a 

 dark red colour. 



The anterior antennæ (see fig. 5) are rather elongated, 

 equalling in length the whole body, minus the caudal 

 rami. They are composed of the usual number of articula- 

 tions, an:l in the living animal are generally extended later- 

 ally, with a slight curvature at the base. 



The last pair of legs (fig. 6) differ conspicuously from 

 those in the other species in the poor development of the 

 terminal joint of the outer ramus. This joint is extremely 



