218 University of California Publications in Zoology [Vol. 23 



B. Front not markedly produced beyond outer orbital angles, formed of 

 five unequal teeth; outer teeth larger and more -widely separated 

 from the three median teeth than these are from each other. 



1. Carapace widest at tenth anterolateral tooth; posterolateral margin 



behind it entire, without teeth; anterolateral teeth with more or 

 less prominent serrations anteriorly. Fingers of chelipeds with- 

 out dark color. 



magister, p. 229. 



2. Carapace widest at ninth (sometimes eighth) anterolateral tooth; 



always with at least a rudimentary tenth and sometimes an 

 eleventh tooth behind it on the posterolateral margin. 



a. Anterolateral teeth low, projecting less than one-third the length 



of base, not spiny-pointed. Fingers of chelipeds without 

 dark color. Merus of outer maxillipeds elongated, rounded 

 anteriorly. (These characters, except those of the fingers of 

 the chelipeds, do not hold in very small specimens, for which 

 see key on p. 219.) 



gracilis, p. 232. 



b. Anterolateral teeth not low, projecting more than one-third the 



length of base, often spiny-pointed. Fingers of chelipeds 

 dark-tipped. Merus of outer maxillipeds not elongated, trun- 

 cated anteriorly, 

 i. Carpus of cheliped with two spines, one above at distal end 

 and a second below this on inner angle; hand roughened 

 and armed above with two or . more spines, sometimes 

 inconspicuous. 



a. Anterolateral teeth acute, strongly produced, alternately 



large and small ; carapace pubescent. 

 i. Tenth anterolateral tooth conspicuous, eleventh present; 

 dactyl of cheliped spiny. Carapace strongly areo- 

 lated. 



gibbosulus, p. 226. 



ii. Tenth anterolateral tooth inconspicuous, eleventh not 



present; dactyl of cheliped not spiny. Carapace 



slightly areolated. (Not known north of Half Moon 



Bay.) 



jordani, p. 228. 



b. Anterolateral teeth broadly triangular, not strongly pro- 



duced, subequal. Carapace strongly areolated, not 

 pubescent. (Not known north of San Diego.) 



amphioetus, p. 223. 

 ii. Carpus of cheliped with a single spine above at distal end; 

 hand smooth or granulated, without spines. 



a. Carapace widest at eighth anterolateral tooth, eleventh dis- 



tinct; under parts spotted or blotched with reddish. 



antennarius, p. 224. 



b. Carapace widest at ninth anterolateral tooth, tenth incon- 



spicuous; under parts of uniform light color. (Not 

 known north of Long Beach.) 



anthonyi, p. 227. 



