162 University of California Publications in Zoology [Vol. 23 



Lithodes couesi Benedict 



Plate 28; plate 29, figures 3, 4, and 5 



Lithodes couesi Benedict, Proe. U. S. Nat. Mus., 17, 481, 1894. 



Original Description. — This species reminds one of L. maia [L.]. The largest 

 spines of the carapace are arranged about the margin ; they are slender and sharp. 

 The longest are situated at the outer orbital angles, the antennal angles, the hepatic 

 regions, and three on the margin of the branchial regions. The spines on the 

 intervening spaces of the margin are more numerous and much smaller. The 

 surface of the carapace is set with short, sharp, conical spines. The gastric region 

 is swollen and well defined. The cardiac region is barely indicated between the 

 confluent branchial regions. The depression between the gastric and cardiac 

 regions is very deep. The rostrum is 20 mm. long, and made up as in L. maia, 

 but the terminal portion beyond the distal lateral branches is slender and bifid 

 rather than bifurcate, as in L. maia; the basal branches are a little farther for- 

 ward. The scale is rudimentary; the spine at the outer angle is branched at the 

 base, the branch consisting of a single short, sharp spine on the outer surface. 

 The abdomen is without spines; the spines of L. maia are replaced by tubercles; 

 those of the first segment are very much closer together than the corresponding 

 spines in L. maia. The tubercles on the lower margin of the second segment are 

 low, and somewhat oblong at base ; those in the center of segment are larger. 



The chelipeds are slender and weak. The armature of the fingers of the right 

 hand is slight ; the fingers gape. The fingers of the left hand are long and slender 

 and gape at base. The spines of the chelipeds and ambulatory legs are numerous 

 and arranged about as in L. maia, but are shorter (Benedict). 



Dimensions. — Type, male: length of carapace and rostrum 105 mm.; width of 

 carapace 81 mm. 



Type Locality. — North of Unalaska; 399 fathoms ("Albatross" station 3329, 

 1 male). 



Distribution. — Bering Sea to off San Diego; 301 to 530 fathoms. 



Remarks. — From the Shumagin Banks, Alaska ("Albatross" station 3338), 

 Benedict records three young specimens which he refers to this species "without 

 hesitation. ' ' Eegarding them he says : ' ' The rostrum differs in being bifurcate 

 as in L. maia. It is possible that additional specimens of the adult might show 

 the rostrum to be bifurcate rather than bifid. ' ' This does not prove to be the 

 case, however, for two adult males from off San Diego ("Albatross" stations 

 4400 and 4333) have the characteristic rostrum of the type. Two other young 

 specimens were also taken off San Diego in 500 to 530 fathoms ("Albatross" 

 station 4335). 



Family Galatheidae 



Body shrimp-like. Abdomen bent upon itself but not folded up against the 

 thorax ; tail-fan well developed, adapted for swimming. First legs chelate, greatly 

 elongated, slender. Antennal peduncle four- jointed owing to fusion of true second 

 and third joints; flagellum long. 



Key to the California Genera op the Galatheidae 



I. Latero-inf erior regions of carapace greatly swollen so that epimeral structures, 

 sides of carapace, are visible in dorsal view. Kostrum long and slender, 

 with a supraorbital tooth on either side of the base. Abdomen dorsally 

 unarmed. (From ninety miles southwest of San Francisco southward.) 



Pleuroncodes, p. 163. 



