COMPLETE HAIG : EASTERN PACIFIC PORCELLANIDAE 65 



tonio: Lund Univ. Chile Exped. (Haig). Tumbes: L. H. Plate 

 (Lenz). Bahia de San Vicente: Lund Univ. Chile Exped. (Haig). 



Diagnosis: Carapace vi^ith a few large tubercles anteriorly, plicate 

 posteriorly; no epibranchial spine; front strongly trilobate, lobes about 

 equal in breadth, rounded at tips; carpus over twice as long as wide, 

 proximal two-thirds of anterior margin produced into a strongly pro- 

 jecting lobe, its edge cut into about eight uneven, serrate-edged teeth; 

 merus of walking legs unarmed. 



Description: Carapace with a few large tubercles anteriorly, plicate 

 posteriorly, finely pubescent. Front strongly trilobate, lobes about equal 

 in breadth, narrow, rounded at tips, the median one more projecting, 

 lateral ones diverging. Outer orbital angle produced into a strong, 

 narrow tooth. No epibranchial spine. 



Text-fig. 3. Basal segment of right antennule of 1, Petrolisthes tuberculatus, 

 X 11 ; 2, P. tuber culosus, x 9. 



First movable segment of antenna with a strongly projecting, gran- 

 ular lobe on anterior margin ; second with scattered rough, projecting 

 granules or small tubercles; third nearly smooth; flagellum naked or 

 with vestigial hairs. Outer maxillipeds punctate or faintly rugose. 



Chelipeds granular, finely pubescent. Merus with a strongly pro- 

 jecting pointed lobe on anterior margin. Carpus more than twice as long 

 as wide; about the proximal two-thirds of anterior margin produced 

 into a strongly projecting lamellar lobe, its edge cut into about eight 

 uneven, serrate-edged teeth; surface with a longitudinal crest formed 

 of large granules, flattened in adults and strongly projecting in young; 

 a similar crest on posterior margin, ending distally in a large, strong 

 tooth. Outer margin of manus thin-edged, with a fringe of hairs in 

 young; surface with a longitudinal crest of large granules. Gape of 

 fingers without a trace of pubescence. 



