PART 1 GARTH : PACIFIC OXYRHYNCHA 97 



superior margins armed on each side with a strong spiny projection. 

 The regions, strongly pronounced, covered with tuberclas very close to 

 each other, especially in the hepatic, pterygostomian, and branchial 

 regions ; on these latter the tubercles divided into two series, one situated 

 near the margin of the carapace ; the other occupying its superior surface, 

 and the space existing between these two series entirely smooth. The 

 other regions, such as the gastric and the cardiac, a little less projecting 

 than the preceding: the first armed anteriorly on each side with a strong 

 spine, situated near the external orbital angle, and above it presenting a 

 transverse row of little tubercles, two median ones much more projecting 

 than the others; the second, or the cardiac region, armed with one 

 tubercle; the first [= third, or external] pair of maxillipeds covered 

 with fine granulations; the sternal plastron also covered with fine 

 granulations, disposed in transverse lines. The abdomen of the male, 

 as also that of the female, entirely smooth and presenting a slight 

 longitudinal projection in its median part. The legs, finely granulate, 

 covered with a short and dense grayish down. (Milne Edwards and 

 Lucas, modified) 



Chelipeds of male strong, about one and a half times length of 

 carapace; palms swollen; fingers narrowly gaping except near the ex- 

 tremities; an enlarged tubercle near middle of fixed finger. Ambulatory 

 legs shorter than the chelipeds in adult males ; upper surface of propodites 

 terminating in a rounded lobe, produced beyond the articulation of the 

 falciform dactyli. Basal segment of antenna with two finely granulate 

 crests meeting in an acute anteroexternal tooth visible at the sides of 

 the rostrum. (Rathbun, 1925) 



Material examined: A total of 711 specimens from 13 Velero III 

 stations. (See Table 13) From Sechura Bay to Independencia Bay, Peru. 



Measurements: Largest specimen, a male: length 19.6 mm, width 

 15.6 mm, cheliped 32 mm, chela 14.8 mm, dactyl 7.2 mm, legs 31.5, 

 25.3, 22.3, and 17.5 mm, respectively. Female: length 12.3 mm, width 

 10.0 mm. 



Color in life: Clear bottle-green. (Milne Edwards and Lucas) 



Habitat: Dredged most frequently on bottoms of sand with shell, 

 less frequently on bottoms of rock or mud. On the sandy bottom of 

 Independencia Bay, Peru, it was difficult to say which of two species of 

 Inachinae, Inachoides microrhynchus or Eurypodius latreillei, was the 

 more abundant. Time and again the small dredge disgorged a teeming 

 mass of spider crabs, interspersed with an occasional large Cancer poly- 

 odon or C. plebejus. To maintain its dominance over the larger species, 





