436 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



Subgenus Parthenope Weber 



Lambrus A. Milne Edwards (restricted), 1878, p. 146. Miers, 1886, 



p. 92 (part). Alcock, 1895, p. 260. 

 Parthenope Rathbun, 1910, p. 319; 1925, p. 513. 



Type: Cancer longimanus Linnaeus, 1758, by subsequent designa- 

 tion of Ratbbun (1904b). 



Description: Carapace ovate-pentagonal, with the surface granulate 

 or pustular and but little carinate in the adult. Rostrum exceedingly 

 short. (Alcock) 



Parthenope (Parthenope) hyponca (Stimpson) 

 Plate Z,, Figs. 1, la; Plate 48, Fig. 1 



Lambrus hyponcus Stimpson, 1871a, p. 100. A. Milne Edwards, 1878, 



p. 153, pi. 30, figs. 3-3b. 

 Parthenope (Parthenope) hyponcus, Rathbun, 1910, p. 576. 

 Parthenope (Parthenope) hyponca, Rathbun, 1925, p. 514, pi. 275, figs. 

 4-6. Garth, 1948, p. 30. 



Type: Female holotype, length 15.2 mm, width 17.3 mm, merus of 

 cheliped 15.2 mm, not extant. 



Type locality : Panama ; Capt. J. M. Dow, collector. 



Localities subsequently reported, with collectors: Mexico: Mazatlan 

 (A. Milne Edwards). Panama: Pinas Bay, Askoy (Garth). Ecuador: 

 off Esmeraldas (01° 07' N, 79° 53' W) and W of Cape Santa Elena, 

 Askoy (Garth). 



Atlantic analogue: Parthenope (Parthenope) agona (Stimpson). 



Diagnosis: Carapace broadly ovate, little carinate; front triangular, 

 deflexed. Meri of ambulatory legs denticulate above. A capitate tubercle 

 ventrally at base of each cheliped. Male abdomen with a median tubercle 

 on sixth segment. Male first pleopod cylindrical, of uniform diameter 

 from base to tip, a few setae at mid-point of closed groove ; setae other- 

 wise marginal and terminal. Male second pleopod with a blunt tip and 

 a subterminal swelling in place of a tooth. 



Description: Carapace subrhomboidal in shape, the posterior region 

 being well developed and prominent. . . One low tubercle on the gastric 

 region, two large, prominent ones on the cardiac [region], one small, 

 spiniform one on the posterior margin at the median line, and two 

 rather large ones on the branchial region, the posterior one the taller, 

 and situated close to the posterolateral margin. Besides these tubercles, 

 several other minute ones, roughly arranged in eight or ten longitudinal 



