COMPLETE HAIG : EASTERN PACIFIC PORCELLANIDAE 219 



taken on the coral sand which is also vividly white at this point [Bahia 

 San Gabriel, Isla Espiritu Santo]." (Steinbeck and Ricketts) 



Ecology: "Found under coral and stones at low tide." (Lockington) 

 Hancock Expeditions collectors took them under stones at many inter- 

 tidal stations, and also from coral heads in the tidal zone and to a depth 

 of one fathom. Specimens were recovered by the Zaca Expedition from 

 coral, Pocillopora ligulata, at 25-^ fathoms (Glassell, 1937). 



Of many females collected in January, February, and March, none 

 were ovigerous. The single egg-bearing female seen or reported is in 

 the Hancock Foundation collections, a specimen taken at Ensenada de 

 San Francisco in May. 



Remarks: Glassell (1938a, p. 440) noted that the present species is 

 subject to very little variation, in spite of Lockington's statement that 

 "This species varies considerably." Like Glassell, the present writer has 

 examined a large series of specimens and found much less variation 

 than is indicated in Lockington's description. Glassell (1936, p. 287) 

 suggested that the Lockington account must have been based in part on 

 Megalobrachium smithi (Glassell). From a careful analysis of Locking- 

 ton's description it seems very probable that among the "several speci- 

 mens" in his type series were examples of M. garthi Haig as well. 



Of the four lots of Lockington types in the Paris Museum, one con- 

 sists of two specimens labelled "Pachycheles rotundus Lockington. Cali- 

 fornie — Lockington 6-99 (Type)." Mr. J. Forest informs the writer 

 that the smaller of these specimens, a female 4.0 mm in length by 4.4 

 mm in width, belongs to the species with which Petrolisthes (Pisosoma) 

 sinutmanus Lockington has been identified by Glassell; the larger speci- 

 men, a 5.2 X 5.5 mm female, fits the description of Megalobrachium 

 garthi Haig. The reason for the name ^'Pachycheles rotundus" on the 

 label is a mystery, for no species description was ever published under 

 that name by Lockington or any other author. In any case, the evidence 

 indicates that these two specimens are part of the series from which 

 Lockington described Petrolisthes (Pisosoma) sinuimanus. 



The smaller of these specimens is selected as the lectotype for three 

 reasons : ( 1 ) the greater part of Lockington's description applies to the 

 present species more closely than to Megalobrachium garthi; (2) Glas- 

 sell applied Lockington's name to the present species and designated a 

 neotype; (3) to affix the name sinuimanus to the other extant type 

 specimen would result in reducing M. garthi to synonymy and would 



