COMPLETE HAIG : EASTERN PACIFIC PORCELLANIDAE 69 



onymy with it. (At the same time they listed P. lobifrons H. Milne 

 Edwards in the synonymy of P. tuberculifrons, evidently by error as 

 they also placed the former name in the synonymy of P. tuberculata 

 Guerin). Although they did not so state, H. Milne Edwards and Lucas 

 may have intended the name tuberculifrons as a substitute for tuber- 

 culosa, to avoid confusion of the latter name with tuberculata. How- 

 ever, in spite of the unfortunate similarity of the names of two closely 

 related species, tuberculosa as the oldest available name must stand for 

 the form under consideration. 



Nicolet (1849) properly used the name Porcellana tuberculosa 

 for the species; however, he created further confusion by citing the 

 related species, Porcellana tuberculata Guerin, as "P. tuberculifrons 

 Guerin." It is apparent from his account that he attributed the name 

 tuberculifrons to Guerin by error for tuberculata, and that he was 

 not referring to Porcellana tuberculifrons H. Milne Edwards and 

 Lucas = P. tuberculosus Guerin. 



The name Porcellana tuberculifrons was used for the present species 

 by Dana (1852) and Cunningham (1871). Stimpson (1858) listed it 

 as Petrolisthes tuberculifrons and also as Petrolisthes tuberculosus, hav- 

 ing apparently lost sight of the fact that the two are synonymous. 



Ortmann (1897) returned to the use of the name afflnis for the spe- 

 cies, arguing that since Gray's Porcellana afflnis was undefined, 

 Guerin's Porcellana afflnis is not a homonym. All subsequent writers 

 have followed Ortmann in citing the species as Petrolisthes afflnis 

 (Guerin). However, Gray's description of Porcellana afflnis is suffi- 

 cient to validate it, although so brief that no species can be positively 

 identified with it. (See also under account of Petrolisthes tridentatus.) 

 Guerin's afflnis is therefore not available for the present species. 



The specimen collected by the Velero III at Bahia de San Juan 

 is the first to be reported from Peru. Rathbun (1910) listed the spe- 

 cies from Peru as well as Chile, but the source of her record has not 

 been found. 



Range: Bahia de San Juan, Peru, south to Chiloe, Chile. 



