THE CANCROID CRABS OF AMERICA 235 



K2. Carapace and l^gs deeply eroded. 



Glyptoxanthus, p. 263. 

 J2. Surface nearly smooth. 



K^ Front deeply separated from inner 

 angles of orbit. Antero-lateral 

 teeth and lobes more or less dentic- 

 ulate. Front quadridentate. 



Platyxanthus, p. 279. 

 K2, Front not deeply separated from 

 inner angles of orbit. Antero- 

 lateral teeth or lobes not denticu- 

 late. Outer angle of orbit not 

 dentiform. 

 ♦ L^ Superior inner tooth of orbit 



obsolete. Carapace convex in 

 both directions, thick, broad 

 oval, front not produced be- 

 yond general outline. 



Carpilodes, p. 241. 

 L^. Superior inner tooth of orbit 

 distinct though small. Antero- 

 lateral rim lobate or dentate 

 and continued behind widest 

 part of carapace, its chord 

 longer than posterolateral dis- 

 tance Xanthodius, p. 311. 



B-. Fronto-orbital border half or more than half the greatest width of cara- 

 pace. 

 C^ Antero-lateral margin continued forward and downward to anterior 

 angle of buccal cavity instead of to orbit. 

 D'. Attachment of movable part of antenna to basis concealed. 

 Front forming a projecting hood over antennules. Surface 

 covered with a reticulating pattern of granules. 



Lipaesthesius, p. 270. 

 D^. Attachment of movable part of antenna normal. 



E^ Superior inner orbital tooth separated from the front by a 



notch Medaeus, p. 273. 



E^. Superior inner orbital tooth absent Carpoporus, p. 269. 



C^. Antero-lateral margin continued to orbit. 



D'. Dorsal surface of carapace and exposed surface of chelipeds and 



legs covered with smooth, rounded, convex lobules _ Daira, p. 268. 



D2. Dorsal surface not covered with smooth rounded convex lobules. 



E^ Carapace rough and hairy except on margin of front and 



orbits. A lunate crest above carpus of ambulatory legs. 



Antero-lateral margin spinous Hetetactaea, p. 530. 



E2. Carapace smooth (non-granulate) and bare or nearly so. 

 F'. Carapace transversely oval. 



G^ Antero-lateral teeth strong. 



FD. Five strong antero-lateral teeth including the 

 orbital. Regions well delimited. Fingers 



often spooned Leptodius, p. 296. 



H^. Two antero-lateral teeth behind orbital angle. 

 Regions not at all delimited. Antenna 

 excluded from orbit.. Ectaesthesius, p. 460. 



