392 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.39. 



single widened joint; other legs as in Bomoloclius. Egg-striags wide 

 and long; eggs of medium size, about one hundred in each string. 



Male. — Body smaller than that of the female and similar to the 

 males of the Corycaeidae, The two pairs of antennae and the swim- 

 ming legs are like those of the female; the first maxillary hooks are 

 considerably enlarged and the terminal claw is elongated and strongly 

 curved. The mandibles are stouter than those of the female, espe- 

 cially the basal joints; the first and second maxillae are small and 

 slender. The maxillipeds are large and strong and of the usual pat- 

 tern for the male sex; the basal joint is furnished with powerful 

 muscles and armed with a row of coarse teeth on the inner margin 

 near the proximal end ; the terminal claw is stout, bent in a half circle, 

 so that the tip shuts against the teeth on the basal joint. 



Tijpe-species. — AncJiistrotos gohii Brian. 



('AfKiaTpojroc, barbed or armed with hooks, alluding to the maxil- 

 lary hooks.) 



To this genus belong the type species, gohii, described by Brian in 

 1906, the species designated as Bomoloclius ostracionis by Richiardi in 

 1870, and Claus's genus EucantJius, with the species halistx Claus, 

 and probably marcliesetti Delia Valle, 1884. This last species has 

 never been described to the author's knowledge, and hence we do not 

 know its distuiguisliing characters. It is therefore omitted from the 

 following key. 



ARTIFICIAL KEY TO THE SPECIES. 



a. Exopod of fourth Bwimming legs without setae, its terminal joint prolonged into a 



claw balistse Claus, 1864. 



a. Both rami of fourth swimming legs of normal shape and well armed with plumose 



setae b. 



b. Terminal claw of maxillipeds as long as the basal joint and without filaments; 



abdomen three- join ted, last joint the longest., ostracionis Richiardi, 1870. 



6. Terminal claw of maxillipeds less than one-fourth the length of the basal jointt 



and armed with two filaments longer than the entire appendage; abdomen 



four-jointed, joints equal gobii Brian, 1906. 



Brian established Anchistrotos as a new subgenus under the genus 

 Bomolochus , but there can be no question that it is entitled to be 

 made a separate genus, when one considers the structure of the first 

 antennae, the maxillary hooks, and the maxillipeds. It is, how- 

 ever, very doubtful whether the specimen figured by Brian (PL 12, 

 figs. 1, 2, and 7 to 10) is really a male. It looks much more hke a 

 young female without egg-strings, and it shows no sex distinctions 

 from the female in the first maxillary hooks, the maxilhpeds, or the 

 genital segment. Certainly one or more of these parts ought to be 

 modified in the true male. 



Claus shows such differences clearly in liis species, halistse, and he 

 certainly had both sexes. It is from the male wliich he describes and 

 not from Brian's doubtful specimen that the sex distinctions of the 

 present genus have been drawn. 



