1921] Schmitt: The Marine Decapod Crustacea of California 47 



Characters. — Surface remotely punctate. Eostrum one and one-third to one 

 and nine-tenths as long as rest of the carapace (in small specimens it may be 

 two and one-half times the carapace), slightly ascending, slightly arched above 

 the eyes. Median crest occupying the anterior two-thirds of the carapace, armed 

 with seven to thirteen movable spines, of which three to five are on the carapace 

 and in front of the middle, the anterior spine considerably behind the middle of 

 the rostrum. There is also a subterminal fixed spine; and occasionally two sub- 

 terminal spines, both above, or one above and one below. Greater part of the 

 rostrum unarmed above; lower margin armed with thirteen to sixteen slender 

 spines, larger toward the base of the rostrum. Antennal scale four-fifths to 

 eight-ninths as long as carapace ; blade broadly rounded at the tip and exceeded 

 by the spine. Ischium of first pair of feet is dilated in a thin, broad, laminar, 

 inferior projection which is anteriorly lobiform. Feet of second pair equal, carpus 

 with twenty to twenty-four segments; the right and left carpus may or may not 

 have an equal number of segments ; chela as long as the five adjacent segments of 

 the carpus. Third segment of abdomen moderately produced backward in the 

 middle, forming a lobe in the posterior margin; sixth segment nearly two and 

 one-half times as long as wide, and about two-thirds as long as the telson. 



Dimensions. — Of a specimen measured by Miss Rathbun: length 164 mm.; 

 length of carapace and rostrum 85.7 mm. ; of rostrum 87.6 mm. 



Type Locality.— OS Monte Video, 600 fathoms ("Challenger"). 



Distribution. — From Washington to Mexico, and off Monte Video; 302 to 1084 

 fathoms. 



Family Hippolytidae 



Rostrum almost always a prominent feature, armed with teeth, and laterally 

 compressed, usually well developed, sometimes, however, even shorter than the 

 eye-stalks. Mandibles various, with incisor process and palp, or without either 

 or both. First pair of legs chelate and moderately stout, stouter and shorter 

 than second pair. Second pair chelate, slender, and equal, with segmented carpus. 



Key to the California Genera of the Hippolytidae 



I. Carpus of second pair of legs with more than seven segments. Mandible 

 without incisor process or palp. (Not known north of Santa Barbara.) 



Hippolysmata, p. 49. 

 II. Carpus of second pair of legs with seven segments. Mandible with incisor 

 process and palp of two segments. 



Spirontocaris, p. 50. 

 III. Carpus of second pair of legs with three segments. Mandible with incisor 

 process but without palp. 



Hippolyte, p. 47. 



. Genus Hippolyte Leach 



Carpus of second pair of legs consisting of three segments. Mandible with an 

 incisor process but without a palp. Carapace with a supraorbital spine. 



