PART 1 GARTH : PACIFIC OXYRHYNCHA 469 



from dorsal view, crested, and dentate, especially on lower margins. Male 

 first pleopod long, slender, tapering to an acute tip, basally and apically 

 setose. Male second pleopod almost as long as first, corneous extension 

 occupying almost a third of total length, channeled to blunt tip, a sub- 

 terminal projection. 



Description: Carapace transversely and regularly elliptical; margins 

 thin, slightly dentate, the denticles separated by broad and very shallow 

 sinuses; posterior margin nearly straight in the middle; anterior margin 

 straight and parallel to the posterior margin for a short space outside the 

 eyes ; front projecting horizontally, its margin forming a semicircle ; 

 gastric region elevated, with a broad median depression extending to the 

 front ; anterior lobe of branchial region large and prominent ; the broad 

 space between the branchial region and the anterolateral margin concave ; 

 summits of the elevations and a space along the posterior border tuber- 

 culous, rest of the upper surface smooth ; inferior lateral regions slightly 

 convex and smooth. 



Chelipeds fitting closely to the carapace, the angles projecting into 

 dentate crests ; outer and inferior surface of the hand coarsely granulate. 

 Ambulatory legs short, the angles projecting into thin, dentate crests. 

 Sternum and abdomen deeply vermiculated. (Smith) 



Material examined: None from the American mainland. Four speci- 

 mens from two Galapagos Islands stations, previously reported (Garth, 

 1946), constitute the entire Hancock Foundation series. 



Measurements: Largest specimen, male: length 63 mm, width 97 

 mm, cheliped 67 mm, merus 25.4 mm, manus 36.3 mm, dactylus 23.4 

 mm, height of palm 22.2 mm. Female specimen: length 53 mm, width 

 85 mm, cheliped 53 mm, merus 20 mm, manus 32.5 mm, dactylus 18 

 mm, height of palm 18.5 mm. 



Color in life: The appearance is that of a much eroded rock encrusted 

 with coralline algae. (Garth, 1946) 



Habitat: Beneath rocks at lower low tide. One specimen has serpulids 



attached. 



Depth: Intertidal. Collected with Daldorfia garthi Glassell at Suli- 

 van Bay, James Island, Galapagos. 



Size and sex: Males are from 47 to 63 mm, females from 39 to 53 

 mm in length. 



Breeding: None of the specimens is ovigerous. 



Remarks: The male pleopods figured herewith (see Plate Z 3 , fig. 

 12) further confirm the assignment of this unique genus and species to 

 the Parthenopidae. Pleopod 2 was found to be inserted into pleopod 1 



