506 BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



CHONDRACANTHODES, new genus 



Female. — Head separated from first segment, considerably elon- 

 gated, and strongly deflexed; thorax more or less distinctly 4-seg- 

 mented; first segment bearing first legs only, second and third 

 segments with a stout blunt process on each lateral margin, fourth 

 segment with a similar process at each posterior corner, all the 

 processes directed ventrally. Second segment with a process on the 

 dorsal midline, projecting forward over the first segment; flattened 

 knob,s on the dorsal surface of the third and fourth segments. Uro- 

 some made up of a genital and two abdominal segments, partially 

 fused; caudal rami minute unarmed. First antennae fleshy and 

 1-segmented; second antennae with stout apical claws; mandibles 

 not fringed with teeth; maxilla without a palp; maxilliped 2-seg- 

 mented, with an apical claw. Two pairs of biramose legs, rami 

 cylindrical, 1-segmented. Ovisacs cylindrical, eggs multiseriate. 



Male. — Head fu,sed with the first segment and much larger than 

 the rest of the body; carapace projecting laterally in a rounded knob 

 on each side opposite the mouth; trunk 4-segmented, anal segment 

 the longest ; caudal rami stout, conical, and armed with a minute ter- 

 minal seta. First antenna a single segment ; second antenna project- 

 ing forward, with a stout apical claw, and an accessory claw on the 

 outer margin of the distal segment; maxillae and maxillipeds well 

 developed and uncinate. Two pairs of biramose legs, the rami flat- 

 tened laminae, the exopod armed with small spines, the endopod 

 unarmed. 



Genotype. — Ohrondracanthodes deflexys, new species. 



Remarks. — This new genus may be recognized by the ventral flex- 

 ure of the head, which in the adult is turned at right angles to the 

 body axis. Probably Thomson's ChoTidr acanthus lotellae belongs 

 here, and the United States National Museum has another new species 

 of this genus that will be described later. 



CHONDRACANTHODES DEFLEXUS. new species 



Plate 38 



Occurrence. — A female with an attached male, taken from the 

 gills of the common grenadier (Macrourus hairdii), captured by 

 Kathbun southeast of Marthas Vineyard, July, 1883, is made the 

 type of the new species with United States National Museum No. 

 59779. Two other specimens were obtained from the same host and 

 locality in 1883. Another specimen was taken from the same host 

 in 1883 at Station 2097, Albatross, and still another in 1884 at Station 

 2173, Albatross. 



Color (preserved material). — Body a uniform brownish yellow. 



