Boone, Crustacea, Cruises of "Eagle" and "Ara," 1921-28 119 



The external maxillipeds have the ischium nearly twice as long as 

 the merus, longitudinally channelled, serrate on the inner lateral 

 margin; the merus is bent inward toward the rostrum and bears a 

 single large tubercle on its outer surface which also has many setae; 

 the palp is small. 



The chelipeds are greatly elongated in both sexes and flattened on 

 the upper surface; the meral joint in the female is equal in length 

 to one-half the width of the carapace, whereas in the male the same 

 joint is equal to the width of the carapace; the carpus is about one- 

 fourth as long as the merus and the propodus is a trifle longer than 

 the merus; the fingers are short and deflected; the lower finger is 

 armed with three or four teeth on the cutting edge ; the upper finger 

 is curved to fit upon the lower. The chelipeds are trigonal in cross- 

 section, the upper surface flattish, the outer lateral margin of the 

 merus armed with four or five teeth, that of the carpus with three 

 or four teeth and that of the propodus with nine teeth, which latter 

 are quite coarse and unequal. The inner lateral margins are also 

 serrate, but the teeth are less coarse. There are two or three teeth 

 on the proximal upper surface of the hinged finger. There is an ap- 

 proximately median longitudinal line of coarse granules on the upper 

 surface of the merus and a few other scattered large tubercles, also 

 some on the propodus. 



The ambulatories are very slender, the first or longest pair not 

 reaching to the distal end of the merus of the chelipeds. Each am- 

 bulatory has a slender, curved, acuminate dactyl, which is marked on 

 each side by two deep longitudinal grooves. 



The male abdominal belt has the first and second segments hinge- 

 like, the third, fourth and fifth anchylosed; the sixth segment vaulted 

 and armed with a median spine ; the seventh, rounded distally. 



The female abdominal belt is seven-segmented, broadly ovate, 

 vaulted in the median line. 

 Synonymy. — Lambrus serratus Milne Edwakds, Hist. Nat. Crust., 



vol. 1, p. 357, 1834. 

 Lambrus lupoides "White, List Crust. British Museum, p. 12, 1847. 

 Lambrus crenulatus Saussure, Mem. Soc. Phys. Hist. Nat. Geneve, 

 vol. 14, p. 429, pi. 1, figs. 4-4a, 1858. — Desbonne and Schramm, 

 Crust. Guadeloupe, p. 21, 1867. — Stimpson, Bull. Mus. Comp. 

 Zool., vol. 2, p. 129, 1871. — Gundlach and Torralbas, Ann. Acad. 

 Habana, vol. 36, p. 301, text fig. on p. 303, 1899 (1900) ; reprint, 

 p. 21, pi. 2, fig. 5, 1917. 



