22 (21) Rostrum hairless, evenly toothed along sides and 



with median low carina Family Axiidae 



23 



Figure 45. — Carapace of an axiid, dorsal view. 



23 (22) Eyes normal with pigmented, rounded cornea; outer blade of uropods lacking trans- 

 verse suture distally Axius serratus 



Figure 46. — Axius serratus; A, ocular region, 



lateral view; B, portion of tail fan, 



dorsal view. 



23 (22) Eyes lacking pigment, flattened obliquely on distal surface; outer blade of uropods 



with transverse suture distally Calocaris templemani 



Figure 47. — Calocaris templemani; A, ocular 



region, lateral view; B, portion of 



tail fan, dorsal view. 



24 (18) Abdomen variously developed and with uropods present; or with uropods absent and 

 only 4 pairs of well-developed legs visible; carapace not apparently fused with epistome 

 Section Anomura, hermit crabs, porcellanids, mole crabs, and lithodids 



25 



24 (18) Abdomen permanently flexed beneath thorax; uropods absent and 5 pairs of legs vis- 

 ible; carapace fused with epistome Section Brachyura, true crabs 



30 



17 



