552 BULLETIN 12% UNITED STATES NATIONAL MUSEUM 



Contains only one species, A. scrwposa, ranging from the Indo- 

 Pacific to the west coast of Mexico. 



AETHRA SCRUPOSA SCUTATA Smith 



Plate 195 



^thra scutata Smith, Amer. Journ. Sci., ser. 2, vol. 48, 1869, p. 120 (type- 

 locality, La Paz; holotype in Yale Univ. Mus.). 



(Ethra scrwposa, var. scutata A. Milne Edwards, Crust. Reg. Mex., 1878, 

 p. 170, pi. 31, figs. 2-2e. 



Cryptopodia fornicata Aurivillius, K. Svenska Vet.-Akad. Handl., vol. 23, 

 1888 (1889), p. 60. Not C. fornicata (Fabricius, 1793). 



Diagnosis'. — Carapace elhptical, lateral borders expanded so as to 

 conceal the legs and cut by long, closed fissures into shallow teeth. 

 Angles of chelipeds and legs projecting into dentate crests. 



Description. — Carapace transversely and regularly elliptical; mar- 

 gins thin, slightly dentate, denticles separated by broad and very 

 shallow sinuses; posterior margin nearly straight in the middle; 

 anterior margin straight and parallel to posterior margin for a short 

 space outside eyes; front projecting horizontally, its margin forming 

 a semicircle; gastric region elevated, with a broad median depression 

 extending to the front; anterior lobe of branchial region large and 

 prominent, the broad space between branchial region and antero- 

 lateral margin concave; summits of elevations and a space along the 

 posterior border tuberculous, rest of upper surface smooth; inferior 

 lateral regions slightly convex and smooth. Chelipeds fitting close 

 to carapace; angles projecting into dentate crests; outer and inferior 

 surface of hand coarsely granulous. Legs short; angles projecting 

 into thin, dentate crests. Sternum and abdomen deeply vermicu- 

 lated. (Smith.) 



Measurements. — Male, holotype, length of carapace 35.3, width of 

 same 56.6 mm. (Smith.) Female, Mazatlan, length of carapace 60, 

 width of same 90, length of hand 45 mm. (A. Milne Edwards.) 



Range. — Mexico: La Paz, Lower California (Gulf of California), 

 type-locality; Mazatlan (A. Milne Edwards, Aurivillius). 



Remarlcs.— According to A. Milne Edwards (loc. cit.) this Ameri- 

 can form is only a variety of the Indo-Pacific A. scru/posa (Linnaeus), 

 differing from it in having the carapace less uneven and less rugose, 

 and the ornamentation and fissures of the lateral borders more dis- 

 tinct. Typical scruposa is found in the Indian Ocean, Malay Archi- 

 pelago, New Caledonia and Fiji Islands.^^ 



'* For synonymy and description, see Alcock, Journ. Asiat. Soc. Bengal, vol. 64, 1895, p. 285. 



