PART 1 GARTH : PACIFIC OXYRHYNCH A 167 



Type: Male holotype, length 15.7 mm, width 13.5 mm; not in 

 Geneva Museum, as ascertained by correspondence with the director. 



Type locality: Mazatlan, Mexico; E. Verreaux, collector. 



Localities subsequently reported, with collectors: Mexico: Lower 

 California: L. Diguet, Albatross (Rathbun, 1925) ; Magdalena Bay, 

 C. R. Orcutt, Hassler (Rathbun, 1925), Zaca (Crane). Gulf of Cali- 

 fornia, Mexico: Off Cape Tepopa, 45 fathoms, Albatross (Rathbun, 

 1892, type of Othonia nicholsi) ; off San Francisco [Island?] (Gulf of 

 California?) (Rathbun, 1925, of specimens in British Museum) ; Los 

 Angeles Bay, Mulege Bay, Port [Puerto] Escondido, San Jose Island, 

 and La Paz. W. J. Fisher ( Lockington, as Micippa ovata) ; San Jose 

 Island, California Academy of Sciences (Rathbun, 1924c) ; El Mogote, 

 Steinbeck and Ricketts (Steinbeck and Ricketts) ; Gulf of California, 

 southern part, 10 fathoms, Albatross (Rathbun, 1898). Nicaragua: 

 Realejo [Corinto], Oersted (Rathbun, 1925). Panama: Taboga Island, 

 St. George (Finnegan) ; Saboga Island, Perlas Islands, Mrs. S. D. 

 Sturgis (Boone, as Pitho quinquedentata) . 



Atlantic analogue: Pitho aculeata (Gibbes). 



Diagnosis: Carapace roughly granulate and strongly tuberculate. 

 Five lateral teeth, the second and third united at base, the second and 

 fifth reduced in size. Cheliped of adult male scarcely longer than first 

 walking leg. First free antennal segment very broad. Male first pleopods 

 distally lyre-shaped. 



Description: Male: Carapace ovoid, longer than broad, its anterior 

 margin between the external angles of the orbits very wide. Rostrum very 

 short, notched, orbits advanced, forming a projecting angle pointing up- 

 wards, notched at their middle above, the notch placed between two 

 triangular spines ; a fissure running from the bottom of the notch. Lateral 

 margins of the carapace armed with five spines ; the first remote from the 

 external angle of the orbit, the second and third close to each other. 

 Regions of the test very well marked ; a furrow at the middle of the 

 anterior part of the carapace ; the latter smooth, bearing several tubercles 

 at the summit of its bosses, one placed in front of, another on the hepatic 

 region, two side by side behind the first ones, then three arranged in a 

 triangle on the anterior part of the intestinal [cardiac?] region, one 

 on each side, at the internal angle of the branchial regions; finally 

 several others, very small and dispersed. Inferior margin of the carapace 

 flanged, and near its posterior portion a denticulate transverse line. First 

 article of the external antennae much broadened, bearing an outgrowth 

 at its external angle. Epimeral plates punctate. 



