24 TRUE CRABS OF MONTEREY BAY 



e. Rostrum composed of two long, slender, cylindrical 

 horns, Chorilia 



ee. Rostrum composed of two short, flattened horns. 

 /. Outer margin of basal antennal joint flattened 

 and produced, not spiny. Scyra 



ff. Outer margin of basal antennal joint not pro- 

 duced, spiny. Rhodia 

 dd. No supra-ocular spine. Chionoecetes 



Key to Species of Inachid^ Found in Monterey Bay. 



a. Rostrum simple. 



b. Rostrum slender; ambulatory legs slender, long (equal to at least 

 twice the width of carapace). 

 c. Chelipeds long, slender; dactyl about one-fourth total length 

 of hand. Erileptus spinosus 



cc. Chelipeds moderately short and stout; dactyl about one-half 

 total length of hand. 

 d. Carapace much elongated in front, depressed, not spiny, 

 rostrum long. Podochela hemphillii 



dd. Carapace not elongated in front, not depressed, rostrum 

 short. 

 e. Acute supra-ocular spine, low tubercle on first ab- 

 dominal joint. Anasinms ro stratus 

 ee. No acute supra-ocular spine, prominent spine on 

 first abdominal joint. 



Dasygykis tuherculatus 

 bb. Rostrum stout, blunt; ambulatory legs short (less than twice the 

 width of carapace). No spines on carapace. 



Epialtus bituberculatus 

 aa. Rostrum bifid. 



b. Rostral horns short or moderate (never exceeding one-fourth the 

 total length of carapace), stout, more or less flattened. 

 c. Surface of carapace more or less undulated, smooth. 



d. Margin of carapace not markedly thin and produced. 



Epialtus productus 

 dd. Entire margin of carapace thin and produced in a leaf- 

 like expansion. Mimulus foliatus 



