242 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



Localities subsequently reported: None. Known only from the type 

 locality. 



Atlantic analogue: None. 



Diagnosis: Rostrum elongate, flattened, emarginate. Orbital margin 

 arched but not toothed. Hepatic lobes large, curving outward and for- 

 ward ; hepatic width exceeding branchial. Merus of external maxilliped 

 notched. 



Description: Carapace with a profound depression in front of the 

 gastric region and one on either side of the cardiac [region], forming 

 with the gastric region a prominent median ridge. Branchial regions de- 

 pressed, with a tubercle near the posterolateral angle. Teeth and promi- 

 nences of the carapace generally setose. Rostrum half as long as the post- 

 frontal part of the carapace, and one-third as broad as long, flattened, 

 truncate, and emarginate at the extremity. Tooth of the anterolateral 

 angle half as long as the rostrum and curving forward ; the distance 

 between the tips of these teeth equaling the greatest width of the cara- 

 pace, and one-third greater than the middle width. A small tooth on the 

 lateral margin behind the anterolateral angle. Orbital margin arched but 

 not toothed. [Legs] with an angular or dentated carpus. (Stimpson, 

 1871a, modified) 



Material examined: 3 specimens from 3 stations. (See Table 48) 

 Cabeza Ballena, Gulf of California, and Acapulco, Mexico; Manta, 

 Ecuador. 



Measurements: Female specimen: length 7.15 mm, hepatic width 5.3 

 mm, branchial width 4.35 mm, rostrum 2.2 mm, width 1.1 mm. 



Color in life: Unrecorded. 



Habitat : At Manta, Ecuador, recovered from a reef over which the 

 surf was breaking with considerable force. 



Depth: Shore. 



Remarks: As noted in the synonymy above, the female specimen 

 from Ferrol Bay (Chimbote), Peru, earlier referred by Rathbun (1910, 

 pp. 535, 572, pi. 49, fig. 5) to Stimpson's species, was later described as 

 Eupleurodon peruvianus Rathbun (1924a). A male specimen from 

 Punta Santa Elena, Ecuador (U.S.N.M. No. 70938), subsequently iden- 

 tified by her as E. trifurcatus with a question mark, is here referred to 

 E. peruvianus (Rathbun, 1923a). (See Remarks under that species.) 

 The female specimen from Manta, Ecuador, although not E. peruvianus, 

 also may not be the long lost E. trifurcatus, which has Cape San Lucas 

 as its type locality. It can be made to fit Stimpson's description by adopt- 

 ing the interpretation given below, which seems preferable to describing 



