NO. 1788. NORTH AMERICAN EROASILIDJJ]— WILSON. 391 



First antennse cylindrical, basal joint moderately enlarged and 

 flattened, with a right-angled curve similar to that in BoTnolochus, 

 and armed with a scraggy row of short setae, interspersed with tactile 

 hairs. Second pair distinctly three jointed, second joint nearly as 

 long as the terminal; the latter roughened and tipped with two slen- 

 der processes, nearly as long as the joint itself, and a tuft of spines. 



First maxillary hooks wanting; mandibles and second maxillse 

 slender and two-jointed, the last joint bipartite; first maxillse each 

 armed with three short plumose setae. 



Maxillipeds behind the second maxillae, each made up of a very 

 large and flattened basal joint, bent inwards at a right angle near its 

 center and bluntly rounded, and two smooth setae or spines which 

 arise from the posterior margm near the distal end and extend back- 

 ward parallel with the body axis. 



Each ramus of the first legs contains two widened joints. 



Egg-tubes unknown. 



Type-spedes. — Phagus {Bomolochus) mnursense, Richiardi. 



(Phagus, (fidyoc, a glutton.) 



As already explained (p. 387), this new genus is provisionally pro- 

 posed for Bomolochus mursenx Richiardi, as described and figured by 

 Brian (1906). As will be seen from Brian's figures of the second 

 antennae and mouth-parts, the generic distinction is a valid one pro- 

 vided the maxillary hooks have not been overlooked and there has 

 been no mistake in the sex of the specimens. 



Genus ANCHISTROTOS Brian. 



Anchistrotos gobii, Brian, 1906, p. 33; pi. 12, figs. 1-10. 



Female. — General body form like that of Cyclops; cephalothorax 

 much larger than any of the free segments; the latter diminishing 

 regularly in size. Genital segment enlarged but little; abdomen 

 tapering considerably; anal laminae narrow and short, but well armed 

 with setae. First antennae cylindrical and six-jointed, the basal por- 

 tion enlarged hardly at all, not bent at a right angle, and armed with 

 small setae which are neither widened nor flattened ; there are also no 

 tactile hairs nor chitin processes. Second antennae similar to those 

 of Bomolochus, three- join ted, the second joint very short, the ter- 

 minal claws large. 



First maxillary hooks of good size, with a well developed basal 

 joint and a short and curved terminal claw; mandibles and second 

 maxillae simple, with a smooth terminal joint; first maxillae small, 

 each armed with three short plumose setae. 



Maxillipeds in normal position behind the other mouth-parts, made 

 up of a large basal joint and a curved terminal claw, sometimes bear- 

 ing long setae. Each ramus of the first swimming legs made up of a 



