86 



gradually attenuated behind ; genital segment considerably tumefied ; anal segment 

 exceeding in length the preceding one. Caudal rami about twice as long as they are 

 broad, and scarcely at all divergent, tip transversely truncated, with the setae rather 

 unequal, the innermost but one being, as usual, the longest, and considerably 

 exceeding the tail in length. Anterior antennse almost equalling in length the 

 cephalic segment, and composed of only 18 articulations, the 3 joints of the 

 terminal part being fused together to form a single joint. Posterior antennse 

 comparatively strongly built, with the penultimate joint fully as long as the 

 preceding one and not much narrower; apical spine rather strong. Oral cone 

 pyriform in shape, and only extending to the insertions of the posterior max- 

 illipeds. Mandibles with the masticatory part of the usual narrow lancet-shaped 

 appearance; palp rather fully developed. Maxillae with the lobes less unequal 

 than usual, apical seta; of both lobes rather strong and finely ciliated. Anterior 

 maxillipeds very powerfully developed, with the claw exceedingly strong and 

 curved like a hook at the end. Posterior maxillipeds likewise rather powerful, 

 though somewhat less so than the anterior ones. Natatory legs less fully developed 

 than in most other species, and more or less incurved; their structure, however, 

 quite normal. Last pair of legs with the distal joint oblong in form, and pro- 

 vided, in addition to the 2 apical setae, with a small bristle at some distance from 

 the tip inside. Ovisacs of moderate size, oval in form, and somewhat divergent. 



Male smaller than female, and having the body somewhat less broad. 

 Tail composed of 4 well-defined segments, the anterior of which is greatly 

 tumefied, to form the lateral hollows in which the rather large spermatophores 

 are received. Anterior antennae composed of 17 joints, the last 2 of which 

 admit of being bent upon the preceding part. Posterior maxillipeds with a 

 well-marked palmar prominence near the base of the hand. 



Body in both sexes semipellucid, with a more or less distinct reddish tinge. 



Length of adult female about 1.30 mm., of male scarcely 1 mm. 



Remarks. This form was described by Boeck in the year 1859 under 

 the name of Asterocheres Lilljelorgi. As, however, the term Asterocheres cannot 

 properly be admitted as a generic designation, I propose to use it here as a 

 specific one, substituting it for the original name Lilljeborgi. Hereby two advan- 

 tages are gained, Istly, that the name Asterocheres may be reserved for the 

 present species, though in a somewhat different sense, and 2ndly. that the specific 

 name Lilljebnrgi proposed by Thorell for his species may stand unchanged. 



The present form is a well-marked and easily recognisable species, being 

 especially distinguished by the very broacj and flattened body and the unusually 



