57 



Three distinct species of this genus belong to the fauna of Norway. Mr. 

 Poppe has moreover described a 4th species from the Behring Sea as Z. Aurelii, 

 and another species is recorded by Prof. Brady from the Kerguelen Islands, but 

 it is erroneously identified by him with one of the northern species (Z. spinatus). 



35. Zaus spinatus, Goodsir. 



(PI. XXXI). 



Zaus frpinatue, Goodsir, On several new Species of Crustaceans allied to Saphirina. Ann. Mag. 

 Nat. Hist. Vol. XVI, pag. 326, PI. XI, figs. 18. 



Syn: Zaus spinosus, Claus. 



Specific Characters. Female. Anterior division of body, seen dorsally, 

 oval in outline, though scarcely attenuated behind. Cephalic segment narrowly 

 rounded in front, rostrum slightly prominent, obtuse at the tip. Last pedigerous 

 segment very small and becoming suddenly much narrower than the others. 

 Urosome about half the length of the anterior division, genital segment rather 

 broad, with the lateral parts expanded, and finely setiferous at the edges; the 3 

 succeeding segments rapidly diminishing in size. Caudal rami about as long as 

 they are broad, and obtusely truncated at the tip, the innermost but one of the 

 apical setse rather elongated, exceeding half the length of the body. Anterior 

 antennae moderately slender, almost attaining the length of the cephalic segment, 

 terminal part longer than the preceding joint. Posterior antennae with the ter- 

 minal joint about the length of the basal one, its 3 spines clothed outside with 

 a dense brush of cilia. Posterior maxillipeds with the hand quadrate in form, 

 dactylus comparatively short, with a secondary spine at the base inside. First 

 pair of legs with the distal joint of the outer ramus shorter than the proximal 

 one, and widening considerably towards the end, apical claws bordered on one 

 side with a dense comb-like series of cilia; inner ramus exceeding half the length 

 of the outer and only biarticulate, last joint very small, with a single apical claw of 

 the same appearance as those on the outer ramus. Natatory legs with the spines 

 outside the last 2 joints of the outer ramus bordered on one side with a comb- 

 like series of cilia. Last pair of legs of moderate size, distal joint much smaller 

 than the proximal one, and broadly oval in form; inner expansion of the latter 

 rather broad, with the edge evenly convex and densely ciliated between the seta3. 



Male considerably smaller than female, with the urosome narrower and 

 distinctly 5-articulate. Anterior antennae very strongly built, 6-articulate, 2nd 

 joint quite short, 3rd large, gradually widening distally, penultimate considerably 



8 Crustacea. 



