CHONDRACANTHID^l. 167 



the base to near the apex. Thoracic legs rudimentary 

 and usually in the form of unsegmented lobes. Egg- 

 strings two, usually short, and containing numerous 

 ova, but sometimes elongated and more or less 

 twisted. 



Male. Very small and adherent on the female by 

 means of hooked appendages. Cephalothorax dis- 

 tinct ; limbs more or less articulated. Abdomen 

 segmented. 



In the Chondracanthidee the type of mandible is distinctly 

 different from that of the Caligidse or the Lernseopodidae ; the 

 biting part is composed of a single moderately elongated 

 piece, and is falciform in shape, broad at the base and 

 tapering to the pointed and often attenuated distal extremity ; 

 these biting parts are articulated to a moderately stout base, 

 and curved towards each other at an abrupt or almost a 

 right angle, and both margins are fringed from the base 

 almost to the apex with minute serratures. This type of 

 mandible is rarely met with in species belonging to any of 

 the other families described here. 



Genus 36. CHONDRACANTHUS De la Roche, 1811. 



Syn. Chondracanthus and Lementoma Baird. 



Female. Head usually small, not articulated to the 

 thorax, separated by a constriction which may be 

 distinct or not clearly denned. Thorax short, mode- 

 rately narrow, and indistinctly bisegmented. Genital 

 segment proportionally large, slightly flattened, and 

 divided usually into two portions by a transverse con- 

 striction, more or less distinct, but sometimes indis- 

 tinct, and with the postero-lateral corners prolonged 

 into narrow processes which may be short or mode- 

 rately elongated. Abdomen very small, situated 

 between the lateral processes and composed of one 

 or two segments. 



Antennules moderately large, more or less con- 

 spicuous in front and somewhat rudimentary in 

 structure. Antennas very short and armed with 

 strong terminal hooks. Mandibles falciform, broad 



