61 



Fam. 6. Peltidiidae. 



Characters. Body short, depressed, with greatly incrusted integuments. 

 Cephalic segment large, more or less flattened, rostrum immobile, not defined at 

 the base. Epimeral plates of the 3 succeeding segments, in some cases also of 

 the last, lamellarly expanded. Urosome short and broad, generally bent down- 

 wards. Eye present. Anterior antenna? 6 9 articulate, in male slightly trans- 

 formed. Posterior antenna distinctly 3-articulate, outer ramus comparatively 

 small, biarticulate. Mandibles not very strong, palp slender, bi- or imiramous. 

 Maxilla? comparatively small. Anterior maxillipeds with 3 slender setiferous lap- 

 pets inside, terminal joint incurved and generally armed at the tip with a slender 

 claw. Posterior maxillipeds terminating in a strongly clawed hand. First pair 

 of legs with the inner ramus natatory, the outer distinctly prehensile. Natatory 

 legs with both rami slender, 3-articulate. Last pair of legs of the same appear- 

 ance in the two sexes, biarticulate, more or less falciform, proximal joint scarcely 

 expanded. Ovisac single, rounded, extending in front between the bases of the 

 natatory legs. 



Remarks. In the restriction here adopted, this family is chiefly charac- 

 terised by the short depressed form of body, the short more or less incurved 

 urosome, the immobile rostrum, and the structure of the 1st and last pais of legs. 

 In the structure of the posterior antenna? and the oral parts, well-marked differ- 

 ences from the Harpacticidce are also to be found. The family comprises as yet 

 3 genera, 2 of which are represented in the fauna of Norway. 



Gen. 16. Alteutha, Baird, 1845. 



Syn: Carillus & Sterope, Goodsii-. 

 Peltidium, Brady (not Philippi). 



Generic Characters. Body more or less oval in outline, with the lateral 

 parts of the cephalic segments inflexed ventrally. Epimeral plates of last segment 

 of metasome much smaller and more rounded than those of the 3 preceding seg- 

 ments. Genital segment large and expanded, the succeeding segments of urosome 

 short and tapering rapidly. Caudal rami short and broad, lamellar, each with a 

 strong spine on the lower face, apical setae comparatively short, 3 of them placed 

 close together at the inner corner. Anterior antennae of moderate length, 8- or 



