446 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



nullipores represented, the latter with weed. Mud bottoms are conspic- 

 uously absent. 



Depth: 3-40 fathoms, the above series. 2-70 fathoms (Garth, 1946). 



Size and sex: Males are from 5.7 to 13.7 mm, females from 5.1 to 

 12.0 mm, ovigerous female 10.6 mm, young from 3.2 mm. A small 

 species, maturing at 5 mm. 



Since the Galapagos Islands series contains almost as many specimens 

 as the mainland series, and from fully as many stations, it has been 

 reexamined with the following results: males are from 5.7 to 17.5 mm, 

 females from 6.3 to 17.0 mm, and young to 4.2 mm. While none of the 

 females is ovigerous, specimens from 9.7 to 17.0 mm are post-puberal and 

 show the widening of the abdomen that comes with the puberty molt. 

 Galapagos specimens, then, appear to run larger than those from the 

 mainland. 



Breeding: The single ovigerous female was obtained in the southern 

 part of the Gulf of California in early April. 



Remarks: The unusual range, west coast of Lower California, Gulf 

 of California, Socorro, Clarion, Galapagos, and La Plata Islands, sug- 

 gests that the species has indeed used island "stepping stones" in reaching 

 the coast of Ecuador. 



Parthenope (Pseudolambrus) excavata (Stimpson) 

 Plate Z^, Figs. 5, 5a ; Plate 50 



Lambrus excavatus Stimpson, 1871a, p. 98. A. Milne Edwards, 1878, 



p. 154. 

 Parthenope (Pseudolambrus) excavata, Rath bun, 1925, p. 529, pi. 189. 

 Crane, 1937, p. 65, pi. 5, figs. 16, 17. 



Type: Female (of two specimens) syntype, length 30.5 mm, width 

 35.0 mm, merus of cheliped 17.3 mm, hand 30.5 mm; not extant. 



Type locality: Manzanillo, Mexico; John Xantus, collector. 



Localities subsequently reported, with collectors: Gulf of California, 

 Mexico: Santa Inez Bay, 29 fathoms, Zaca (Crane). Panama: Panama, 

 Capt. J. M. Dow (Rathbun). 



Atlantic analogue: None. 



Diagnosis: Lateral margins angled. Angle of deflection of rostrum 

 90°. Dorsal tubercles low, granulate ; interspaces, 5 on the anterior half 

 of the body, deeply excavated. Chelipeds concave above, surface between 

 crests smooth. Three paired, flat sternal spines. Ambulatory legs crested 

 above. Male first pleopod cylindrical, little tapering, tip emarginate, a 





