114 University of California Publications in .Zoology [Vol.23 



Characters. — Carapace (rostrum included), measured in the middle line, as 

 long as the first five abdominal somites; its surface pitted, especially on the 

 inferolateral portions, a few feeble setae springing from the pits; cervical groove 

 deep, branchial grooves indistinct. The rostrum reaches to the end of the second 

 joint of the antennular peduncle and is tipped with a spine; its lateral margins 

 are armed with three to seven spines ; the prolongations of these margins are armed 

 with five to six spines, and form a horseshoe on the carapace which is open behind 

 and outlined in front by a groove a little posterior to the orbit. The median 

 carina extends from the middle of the rostrum to the rear of the horseshoe and is 

 from two- to six-, usually three-spined at its middle. Between the median carina 

 and the sides of the horseshoe is another row of three to five spines. The cheli- 

 peds are unequal, the longer one in the male nearly as long as the body; setose; 

 its inner surface and also the outer surface of carpus and hand covered with 

 sharp granules or short spines ; upper margin spinose, also lower margin of merus ; 

 lower outer margin of merus outlined with very short, blunt spines and a single 

 longer distal spine; lower margins of propodus armed with dentiform granules, 

 margins subparallel. Fingers shorter than palm in adult males, just as long as 

 palm in smaller males and females; usually slightly gaping at base; occludent 

 edges finely and irregularly dentate. The stouter cheliped may be longer or shorter 

 than the slender one. In the female the chelipeds are two-thirds as long as the 

 body. 



Dimensions. — Type, male: length of carapace and rostrum 28 mm., of abdomen 

 41 mm. 



Type Locality. — Off San Luis Obispo Bay, 200 fathoms ("Albatross" station 

 3196). 



Distribution. — Also taken by the "Albatross," off Point Sur, 298 fathoms; 

 off San Simeon Bay, 160 fathoms; off San Luis Obispo Bay, 252 fathoms; off 

 Point Conception, 233 to 284 fathoms; Santa Barbara Channel, 205 to 280 

 fathoms ; off Anacapa Island, 388 fathoms, and off San Nicolas Island, California, 

 1084 to 1100 fathoms. 



Family Callianassidae 



Body shrimp-like. Abdomen extended; abdominal pleura small or absent; 

 tail-fan well developed and adapted for swimming. First pair of legs unequal 

 or subequal, perfectly or imperfectly chelate; third and fourth pairs simple, others 

 variable. Antennal peduncle five-jointed; antennal scale quite vestigial; no 

 antennal thorn. 



Key to the California Genera of the Callianassidae 



I. Bostrum of good size, though short, tridentate, rough and hairy. First pair 

 of legs subequal, with very small pollex, tending to become subchelate ; none 

 of remaining pairs chelate. Eye peduncles cylindrical. External maxilli- 

 peds pediform. 



Upogebia, p. 115. 



II. Bostrum small, reduced to a small point or absent. First pair of legs very 

 unequal, with well developed chelae; second pair small and chelate; fifth 

 pair subchelate. Eye peduncles flattened. External maxillipeds opereuli- 

 form. 



Callianassa, p. 116. 



