COMPLETE HAIG : EASTERN PACIFIC PORCELLANIDAE 17 



members of that genus, especially in the form of the carapace and front ; 

 in Porcellana, however, the basal antennal segment is broadly in con- 

 tact with the anterior margin of the carapace. The combination of 

 characters given in the description, above, sets Liopetrolisthes apart 

 from all other genera in which the basal antennal article lacks a strong 

 forward projection in contact with the carapace margin. 



The generic name is derived from the Greek Acio?, smooth, and 

 Petrolisthes. 



Liopetrolisthes mitra (Dana), new combination 

 Frontispiece; plate 41, fig. 1 ; text-fig. 2 



Porcellana mitra Dana, 1852, p. 419 (type locality, San Lorenzo, Peru) ; 

 1855, pi. 26, figs. 9a-b. Heller, 1865, p. 74. Cano, 1889, pp. 96, 

 101, 260. Rathbun, 1910, p. 601. Meredith, 1939, p. 113, col. pi. 



Plorcellanal mitra?, Stimpson, 1858, p. 229. 



Porcellana spinosa Philippi, 1860, p. 169 (type locality, Isla Blanca, 

 Chile). 



Porcellana patagonica Cunningham, 1871, p. 495 (type localities, 

 Estrecho de Magallanes and Port Otway [Puerto Barroso], Chile). 



Porcellana pulchellula Cano, 1889, p. 260 (type locality, San Lorenzo, 

 Peru). Rathbun, 1910, p. 601. 



Petrolisthes patagonicus, Lenz, 1902, p. 748, pi. 23, fig. 4. Bouvier, 

 1906, p. 28. Rathbun, 1910, p. 600. Doflein and Balss, 1912, p. 34. 

 Porter, 1926, p. 190, text-fig. 23; 1936a, p. 255; 1936b, p. 153; 

 1936c, p. 339. 



Petrolisthes mitra, Haig, 1955, pp. 43, 52. 



Previous records: 



Peru. San Lorenzo: U. S. Expl. Exped. (Dana) ; Vettor Pisani (Cano). 

 Bahia de la Independencia: Velero III (Meredith). Mollendo: R. 

 Paessler (Haig). 



Chile. Pisagua: Kophamel (Haig). Iquique: L. H. Plate (Lenz) ; F. 

 Ringe (Doflein and Balss; Haig). Cavancha; Tocopilla: Lund 

 Univ. Chile Exped. (Haig). Isla Blanca: R. A. Philippi (Philippi). 

 Caldera: R. Paessler (Haig). Peninsula Coquimbo: Lund Univ. 

 Chile Exped. (Haig). Montemar: F. Riveros-Zuniga (Haig). Val- 

 paraiso: C. E. Porter (Bouvier; Porter 1926). Curaumilla: C. E. 

 Porter (Bouvier; Porter 1936a). Golfo de Arauco: Lund Univ. 



