98 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 24 



(Haig). Chiloe: Vettor Pisani (Cano). Ancud, Isla Chiloe: Nassau 

 (Cunningham). Isla Clotilde, Archipielago de Chiloe: Alva (Boone). 

 Chonos: Vettor Pisani (Cano). Archipielago de Los Chonos: Lund 

 Univ. Chile Exped. (Haig). Canal Messier: Challenger (Henderson). 



Diagnosis: Carapace nearly smooth, very strongly convex front to 

 back; no epibranchial spine; front triangular; carpus one and a half 

 to a little less than two times as long as wide, anterior margin with a 

 strong proximal lobe, margins converging distally from its highest 

 point ; outer margin of manus with a sharp crest, outer half of dorsal 

 surface with a short pubescence ; merus of walking legs unarmed, that of 

 leg 3 somewhat inflated. 



Description: Carapace very strongly convex front to back, nearly 

 smooth or with very fine granules anteriorly, granules not transversely 

 elongate as in Petrolisthes granulosus; posterolateral regions with light 

 plications. Front triangular, strongly produced, with a shallow median 

 sulcus; no supraocular spine; inner orbital angle not produced. Orbits 

 shallowly concave; outer orbital angle produced into a narrow, distinct 

 tooth. No epibranchial spine. Carapace naked or with traces of a fine 

 pubescence anteriorly. 



First movable segment of antenna granular, with a narrow lamellar 

 projection on anterior margin ; second and third granular ; flagellum 

 with long hairs. Outer maxillipeds lightly rugose or punctate. 



Chelipeds covered with small granules, appearing nearly smooth. 

 Merus with a strongly projecting granular lobe on anterior margin. 

 Carpus one and a half to less than two times as long as wide, lightly 

 pubescent; a strong lobe at proximal end of anterior margin, anterior 

 and posterior margins converging distally from its highest point; pos- 

 terior margin with a low, obliquely rugose ridge ending distally in a 

 small tooth. Outer half of dorsal surface of manus with a short, thick 

 pubescence, continuing for a short distance onto pollex; outer margin 

 with a smooth, sharp crest. Gape of fingers with a short pubescence, 

 not produced into a tuft. 



Walking legs nearly smooth to lightly granular. Merus unarmed, 

 with a short fringe of plumose hairs on anterior margin, that of leg 3 

 somewhat inflated. Carpus, propodus, and dactylus with scattered short 

 tufts of setae. 



Material examined: See Table 28. 



Measurements: Males, 5.1 to 23.9 mm; non-ovigerous females, 7.6 

 to 17.6 mm; ovigerous females, 8.8 to 16.7 mm. All these measurements 



