468 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



Description: Carapace oval, embossed, and a little elevated on its 

 periphery. Front little advanced. Eyes very small, lodged in circular 

 orbits. Basal article of the antennae elongated and joined to the front 

 by its internal angle; flagellum small and lodged in the orbital hiatus. 

 Basal article of the antennules broad and almost quadrilateral in form. 

 Buccal cavity narrowed anteriorly, epistome short, and external maxilli- 

 peds strongly elongated; their merus truncate anteriorly and outside, 

 presenting no emargination for the insertion of the palpus. Legs, entirely 

 concealable under the margin of the carapace, compressed and having 

 cristiform ridges. 



Abdomen of the male divided into five articles; that of the female 

 into seven. (A. Milne Edwards, modified) 



Chelipeds about equal in length to the carapace; having . . . sharply 

 prismatic [segments] and large inturned fingers, but concave on the 

 upper surface. (Alcock) 



Range: Eastern Pacific at La Paz, Gulf of California, and Mazatlan, 

 Mexico; Galapagos Islands. Indo-Pacific from East Africa to New 

 Caledonia and Fiji Islands; Japan (Salcai). 



Aethra scruposa scutata Smith 

 Plate Za, Figs. 12, 12a ; Plate S3 



Aethra scutata Smith, 1869b, p. 120; 1869c, p. 230. 



Oethra scruposa, var. scutata, A. Milne Edwards, 1878, p. 170, pi. 31, 



fig. 2-2e. 

 Cryptopodia fornicata, Aurivillius, 1889, p. 60. Not Cancer fornicatus 



Fabricius. 

 Aethra scruposa scutata, Rathbun, 1925, p. 552, pi. 195. Garth, 1946, 

 p. 415, pi. 70, figs. 1, 2. 



Type: Male holotype, length 35.3 mm, width 56.6 mm; in Yale 

 University Museum (Rathbun, 1925). 



Type locality: La Paz, Lower California, Mexico; Captain Peder- 

 sen, collector. 



Localities subsequently reported, with collectors: Mexico: Maza- 

 tlan (A. Milne Edwards, Aurivillius). Ecuador: Hood Island and James 

 Island, Galapagos Islands, Velero III (Garth). 



Atlantic analogue: None. Affinities are with the Indo-Pacific, where 

 Aethra scruposa (Linnaeus) occurs. For synonymy and description see 

 Alcock (1895, p. 285). 



Diagnosis: Carapace broadly elliptical, front arcuate, lateral mar- 

 gins lamellate, dentate, incised. Chelipeds and walking legs concealed 



