102 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 24 



blue, segments margined with grenadine red. Ventral side light caeru- 

 lean blue. (Petersen, of a live specimen from Peru) 



Purple patches irregularly arranged on a yellowish-red ground. 

 Chelipeds purple, the segments and borders of the fingers and hands 

 edged with a narrow salmon-red border. Walking legs prettily banded 

 with purple and yellowish-red ; under parts much lighter in color. 

 (Kinahan, of a specimen preserved but a few years) 



After long preservation in alcohol, many specimens retain a brown- 

 ish-red color on the carapace and distinct stripes on the propodus and 

 dactylus of the walking legs. Some retain a deep blue or violet color 

 on the metabranchial regions, even when all other color has entirely 

 disappeared. 



Ecology: This species is apparently restricted to an under- rock 

 habitat in the intertidal zone, where it is one of the commonest crusta- 

 cean species of the Peruvian faunal province. Ovigerous females are 

 reported for December, January, February, and June.. 



Remarks: Among the dry collection in the Academy of Natural 

 Sciences of Philadelphia is a specimen of Petrolisthes violaceus 

 which, according to the label, is questionably a type and was collected 

 by the Coquille at Valparaiso. Talcahuano was the only locality men- 

 tioned by Guerin for this species from the Coquille collection. 



Two dry specimens in the Academy of Natural Sciences of Phila- 

 delphia are labelled "Galapagos Islands," as previously noted by Ort- 

 mann (1897). This locality is in all probability in error, for the spe- 

 cies is not otherwise known from the Galapagos archipelago. 



Range: Callao, Peru, south to Taitao, Chile. 



Petrolisthes holotrichus Nobili 

 Plate 29, fig. 4 



Petrolisthes holotrichus Nobili, 1901b, p. 14 (type locality, Isla Fla- 

 menco, Panama). Rathbun, 1910, p. 599. Haig, 1957b, p. 8. 



Previous records: Panama. Isla Flamenco: E. Festa (Nobili). 

 Isla Pacheca, Islas de las Perlas: Askoy (Haig). 



Diagnosis: Carapace nearly smooth, it and rest of body com- 

 pletely covered with a short, fine tomentum; no epibranchial spine; 

 front trilobate ; carpus less than twice as long as wide, anterior margin 

 with a strong proximal lobe, margins converging distally from its 

 highest point; outer margin of manus with a thin edge, and with to- 



