372 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



Miers' Chilean record has been traced by means of White's (1847) 

 List of Crustacea in the British Museum to a young specimen from the 

 Bell collection. If this were one of the type series, as seems probable, the 

 Chilean locality is in error and Mithrax (Mithrax) belli has always 

 been a Galapagos endemic species. 



Subgenus Mithraculus White 



Mithrax (Mithraculus) Rathbun, 1925, p. 421. 



Description: Carapace with conspicuous, smooth, oblique, branchial 

 sulci. Rostral horns very short, shorter than wide, truncate. Minor teeth 

 of orbit tuberculiform, inconspicuous. (Rathbun) 



With the uniting of Mithrax areolatus Lockington with M. denticu- 

 latus Bell by Crane (1947, p. 73), there are now but two species in the 

 eastern Pacific belonging to this, the smaller subdivision of the genus. 



Mithrax (Mithraculus) denticulatus Bell 

 Plate V, Fig. 9; Plate 42, Fig. 2 



Mithrax denticulatus Bell, 1835b, p. 172; 1836, p. 54, pi. 11, figs. 2, 



2c-e. Miers, 1886, p. 87. Rathbun, 1892, p. 272; 1907, p. 74; 



1910, p. 575. Nobili, 1901, p. 31. Crane, 1947, p. 73. 

 Mithraculus denticulatus, White, 1847, p. 7. Stimpson, 1860b, p. 187. 



A. Milne Edwards, 1875, p. 109; 1878, pi. 23, figs. 4, 4a-c. Bouvier, 



1895, p. 8. 

 Mithrax areolatus Lockington, 1877c, p. 71 ; type locality, Port [Puerto] 



Escondido and San Jose Island, Gulf of California; types not 



extant. Miers, 1886, p. 87. Rathbun, 1910, p. 575. Steinbeck and 



Ricketts, 1941, p. 467, pi. 29, fig. 1. 

 Mithraculus areolatus, Streets and Kingsley, 1877, p. 104. Kingsley, 



1879a, p. 146. 

 Mitraculus areolatus, Cano, 1889, pp. 102, 186. 

 Mithrax (Mithraculus) denticulatus, Rathbun, 1925, p. 428, pi. 154, 



figs. 2, 3. Boone, 1927, p. 161, fig. 51. Garth, 1946, p. 395. 



Buitendijk, 1950, p. 274. 

 Mithrax (Mithraculus) areolatus, Rathbun, 1925, p. 433, pi. 154, fig. 1. 



Crane, 1937, p. 61. 



Type: Bell's type material consisted of the figured female and an 



unspecified number of cotypes ; length of measured cotype 10.6 mm, 



width 12.7 mm; these were originally deposited in the Museum of the 



Zoological Society [London] and in the Bell Museum, but are no longer 



