83 



(in female) somewhat dilated in the middle, 9-articulate, terminal part abruptly 

 narrowed. Posterior antennae with the outer ramus less fully developed than in 

 Aspidiscus. Mandibles, maxillse and anterior maxillipeds of a structure very similar 

 to that in the above-named genus. Posterior maxillipeds, however, differing in the 

 presence of 3 strong claws at the tip. First pair of legs, as in Aspidiscits, very 

 delicate, with both rami 3-articulate, though differing conspicuously in structure 

 from those in that genus, outer ramus much shorter than the inner, with the 

 terminal joint very small, and carrying on the tip a number of closely-disposed 

 pulvilliform spines; inner ramus with the 2nd joint well developed, the last one 

 carrying 2 densely fimbriate spines. Natatory legs with the middle joint of the 

 inner ramus in all pairs carrying 2 setae. Last pair of legs less strongly built 

 than in Aspidiscus, proximal joint comparatively short and bilobed at the end, 

 distal joint oblong, lamellar. Ovisac normal. 



Remark*. This genus was established by Philippi in the year 1840, to 

 include a species found by him in the Mediterranean at Sorrento. The genus 

 Scutellidium of Glaus is unquestionably identical with Philippi's genus, and as 

 that name is of much later date, it must cede the place to that proposed by 

 Philippi. The genus is nearly allied to Aspidiscus, but differs in some characters 

 rather conspicuously, both as regards the external appearance of the body and 

 the anatomical details. In addition to the typical species, 2 other closely-related 

 forms have been described, the one, Scutellidium Arthur i Poppe, from the Behring 

 Sea, the other, 8. plumosum Brady, from New Zealand. 



50. Psamathe longicauda, Philippi. 



(PI. XLIX). 

 Psamalhc luiKj'iatwla, Philippi. in Wiegm. Archiv f. Natuvgesch. 1840, p. 189. PI. IV, iig. 1. 



Syn: Scutellidium thisboides, Claus. 



Specific Characters. female. Anterior division of body moderately ex- 

 panded, oval in form, and scarcely at all narrowed behind. Cephalic segment 

 occupying about half the length of the anterior division, and gradually contracted 

 anteriorly, front narrowly rounded. Epimeral plates of the 3 succeeding segments 

 of moderate size, discontiguous at the tips; 4th segment rather broad, with tlir 

 posterior edge only very slightly incurved in the middle. Last segment of meta- 

 sorne extremely small, but wholly uncovered. Urosome about half the length of 

 the anterior division, and gradually tapered behind; genital segment somewhat 

 dilated in front, and imperfectly divided in the middle, lateral edges in this and 



