KEY TO SPECIES OF INACHID^L 2$ 



cc. Surface of carapace markedly tubercular or spiny. 



d. Carapace sub-pyriform or lyrate, rostrum moderate or 

 long (one-fourth to one-sixth total length of car- 

 apace). 



e. Rostral horns extremely flattened and leaf-like, not 

 markedly divergent in adult. 



Scyra acutifrons 

 ee. Rostral horns never greatly flattened, more or less 



divergent. 



/. Carapace undulated, with few moderate tubercles. 



g. Post-ocular spine and first antero-lateral 



tooth united by a leaf-like expansion of 



the carapace. Pugettia gracilis 



gg. Post-ocular spine and first antero-lateral 



tooth acute and distinct. Pugettia richii 



ff. Carapace with numerous or very prominent 



tubercles. 



g. Tubercles small and numerous, carapace 

 markedly convex. Loxorhynchus grandis 

 gg. Tubercles comparatively few, large and 

 prominent, carapace not convex. 



Loxorhynchus crisp at us 

 dd. Carapace sub-orbicular, rostrum very short (one-ninth 



or one-tenth of total length of carapace). 

 e. Ambulatory legs long (equal to twice the width of 

 carapace), no supra-ocular spine. 



Chionoecetes tanneri 



ee. Ambulatory legs moderate (about equal to once 

 and a half the width of carapace), an acute 

 supra-ocular spine. Rhodia parvifrons 



bb. Rostral horns long (about one-third the total length of carapace), 

 slender, cylindrical. Chorilia longipes 



