94 



Gen. Psammis, G. O. Sars. 



Remarks. This genus was established by the present author in the 

 year 1911, to include a single species of which at that time only 2 female 

 specimens had come under my notice. I have subsequently had an oppor- 

 tunity of examining also a fully adult male specimen, and, as the sexual diffe- 

 rences in this form are rather striking, both as regards the outward appearance 

 and the structure of some of the appendages, I have found it advisable to give 

 below a full description of the specimen accompanied by figures of the whole 

 animal and of some of the structural details. 



76. Psammis Songisetosa, G. O. Sars. 



(PI. LXV). 

 See Vol. V, p. 339, PI, CCXXV. 



Specific Characters. Male. Body considerably more slender than in 

 female and gradually tapered behind. Cephalic segment about occupying half 

 the length of the anterior division, and provided in front with a well-defined 

 and rather prominent rostral plate of regularly oval form, with 2 delicate sen- 

 sory hairs on each side. Urosome about equalling in length 3 A of the anterior 

 division, and composed of 5 well defined segments, the 4 anterior of which 

 are of about equal size; last segment considerably smaller and somewhat 

 widening distally, with the anal opercle inconspicuous. Caudal rami consider- 

 ably divergent, with the apical setae greatly prolonged. Anterior antennae very 

 strongly built and conspicuously hinged, being apparently composed of 7 joints, 

 the penultimate of which is strongly inflated, almost globose in form; terminal 

 joint narrow unguiform and very mobile, admitting of being impinged against 

 the anterior face of the preceding joint, both together forming a very powerful 

 grasping organ. Posterior antennae and oral parts scarcely different from those 

 in female. 1st pair of legs also rather similar, only differing in the shape of 

 the spine issuing from the inner corner of the 2nd basal joint, this spine 

 being not, as in the female, straight, but distinctly curved inwards. 2nd pair 

 of legs with the inner ramus conspicuously transformed, each of the joints 

 being produced at the end outside to a well defined acuminate process, that 

 of the middle joint being much the largest, mucroniform, and extending almost 

 to the end of the terminal joint. The 2 succeeding pairs of legs of the very 

 same structure as in the female. Last pair of legs however very different, the 

 distal joint being not, as in the female confluent with the proximal one, but 



