THE SPIDER CRABS OF AMERICA 383 



Mithrax spinifrons A. Milne Eidwsirds = ScMzopTirys aspera (Milne 

 Edwards) . 



Mithrax triangularis K.ossm&nn = Schizophrys aspera (Milne Ed- 

 wards) . 



Mithrax suhorhicularis Stimpson = Cyclax suhorhicvlaris (Stimpson) . 



Subgenus Mithrax 



Carapace without conspicuous, smooth, oblique, branchial sulci. 

 Rostral horns usually as long as wide, sometimes elongate and spini- 

 form. Minor teeth or tubercles of orbit plainly marked, though 

 small. 



MFTHRAX (MITHRAX) SPINOSISSIMUS (Lamarck) 



CANGREJO DE LA SANTA VIRGEN (Cuba); CABOUCA (Martinique) 



Plate 135 



The Lazy Crab Hughes, Nat. Hist. Barbados, 1750, p. 262, pi. 25, fig. 1 (part: 



chelipeds and legs only). 

 Cangrejo Santoya Parra, Descripcion de diferentes piezas de historia natural, 



1787, p. 122, pi. 44. 

 f Cangrejo Denton Parra, Descripcion de diferentes piezas de historia natural, 



1787, p. 136, pi. 51, fig. 1. 

 Maia spinosissima Lamarck, Hist. Nat. des Anim. sans Vert., vol. 5, 1818, 



p. 241 (type-locality, Ile-de-France; type in Paris Mus.). Locality 



erroneous. 

 Mithrax spinosissimus Milne Edwards, Mag. ZooL, vol. 2, 1832, classe 7, 



pi. 2 (colored) and 3 and description (Antilles; Martinique). — -Rathbun, 



Proc. U. S. Nat. Mus., vol. 15, 1892, p. 261, and synonymy. — Gundlach 



and ToRRALBAS, An. Acad. Habana, vol. 36, 1899 (1900), p. 305, text-fig. 



on p. 326; reprint, 1917, p. 14, pi. [3J, fig. 7. 

 Mithrax hispidus Doflein (not Herbst), Sitz. k. bayer. Akad. Wiss., math.- 



phys. CL, vol. 29, 1899, p. 179; St. Pierre, Martinique, 4 to 5 fathoms. 



Diagnosis. — Large, carapace without lateral angle. Three supra- 

 orbital spines between preorbital and postorbital spine. Fifth lateral 

 spine in line with gastro-cardiac suture. No spine on basal antennal 

 segment at articulation of next segment. 



Description of adult. — Carapace nearly naked, subcircular, about as 

 broad as long; cervical suture deep; hepatic and cardiac regions dis- 

 tinctly delunited; surface rough with short spines, those in the center 

 of the carapace blunt, those elsewhere sharp. Rostral horns nar- 

 row, extremity obliquely truncate and granulate, separated by a 

 U-shaped sinus of equal length and breadth; at base of horns, two 

 stout spines and behind these, two others similar but farther apart. 

 Preorbital spine stouter than rostral horn, truncate and much less 

 advanced than rostrum; between this and the truncate postocular 

 lobe there are three smaller teeth; on the suborbital margin one acute 

 spine outside the antennal segment; two spines on the antennal seg- 



