of the body looks rather different, and more resembles that in some forms 

 belonging to the next family. In the structure of the several appendages it 

 seems to come nearest to the genus Pteropygus, but differs conspicuously in 

 the general form of the body and its less distinctly marked segmentation, as 

 also very essentially in the structure of the tail. The genus comprises as yet 

 only a single species, to be described below. 



24. Schizoproctus inflatus, Aurivillius. 



(PI. XXXIV) 



Schizoproctus inflatus, Aurivillius, Krustaceer hos atktiske Tunicater, Vega Expeditionens veten- 



skaplige Arbeten, p. 248, PI. 9, figs. 21-32. 



Specific Characters. Female. Body oblong fusiform in shape and rather 

 tumid in the middle, but gradually narrowed both in front and behind; dorsal 

 face evenly vaulted. Tail about equalling in length 2 /a of the anterior division 

 and somewhat tapered distally, last segment nearly twice the length of the 

 preceding one and narrowly rounded at the extremity. Caudal rami compara- 

 tively small, each armed with 4 short, somewhat unequal claws. Anterior 

 antennae very short and stout, composed of only 4 joints clothed in front with 

 comparatively short spiniform setae of unequal length. Posterior antennae shorter 

 and stouter than in the 2 preceding species, terminal joint armed outside with 

 3 short spines and at the broadly truncated extremity with 3 similar spines 

 followed by 2 thickish setae. Mandibles and maxillae of essentially same struc- 

 ture as in Pteropygus. Anterior maxillipeds however considerably shorter and 

 stouter, with an additional small seta inside the base; seta of 3rd joint replaced 

 by a claw-like spine. Posterior maxillipeds very thick at the base, with the 

 posterior edge of 1st joint coarsely serrate. The 4 anterior pairs of legs with 

 both rami short, triangular in form, the outer one armed outside with 5 stout 

 spines. Last pair of legs, as in Pteropygus, broad, mantle-like and approx- 

 imate dorsally. 



Male of dwarfy size, scarcely exceeding in length Vs of the female, and 

 found attached to the ventral face of her genital segment. Body somewhat 

 depressed and gradually attenuated behind, with all the segments sharply de- 

 fined, the genital one rather swollen and containing on each side a pear- 

 shaped spermatophore. 



Colour not yet ascertained. 



Length of adult female 6.10 mm, of male 1.30 mm. 



Remarks. 7 he present remarkable form was described by Aurivillius in 



