130 



BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



the fourth pair with numerous stout spines along- its internal edg-e, 



these beeoming fewer and weaker on posterior pairs, which are more 



abundantly furnished with long slender seta?, 



the lifth joint of last pair of legs broad and 



almost rectangular. 



''Abdominal appendages suljsimilar, the iiro- 

 pods not projecting beyond the margin of tel- 

 son, attached to underside, in structure similar 

 to the pleopods and probably l)ranchial in 

 function. 



"Color gray, with arborescent brown pigmen- 

 tation becoming more dense posteriorh% on 

 abdomen collected principally in a median 

 wedge-shaped mass with the apex on base of 

 telson, each segment of pleon with two subellip- 

 tical paler lateral areas, with about twenty-five 

 to thirty longitudinal lines of pigmentation, the 

 areas l)etween which are reticulated with brown. 

 Mandibles, legs, and underside of body more 

 or less pigmented. 



"One specimen, from station 6079, 20 fath- 

 oms, by 2.2 mm."' — Moore." 



Fig. 111.— Branch ["ROprs 

 I, I T TO 11 A L I s (After 

 M(K)RE). Uropuda from 



BELOW. 



24. Genus BATHYNOMUS A. Milne Edwards. 



Second pair of antenna? with a peduncle composed of five articles:'^ 

 rudimentary scale attached to end of peduncle of first antennae. 



The plate of the second article of the maxillipeds furnished with 

 hooks. 



Abdomen with all six segments distinct. 



Pleopoda with supplementary ramified bi-aiichia> developed at the 

 base of the imier branches. 



BATHYNOMUS GIGANTEUS A. Milne Edwards. 



Bat}ii/noiiiii>f (jifjaiileux A. Milne Edwards, Coiiipt. Rend. Acad. Si;i., LXXXVIII, 

 1879, pp. 21-23; Ann. Mag. Nat. Hist. (5), III, 1879, pp. 241-243.— Filhol, 

 La vie au fond des Mers, 1885, p. 147. — Marshall, Die Tiefsee und ihr 

 Leben, 1888, p. 261, fig. 86.— Agassiz, Bull. Mus. Conip. Zool., Harvard 

 College, XV, 1888, p. 49, fig. 252.— Hansen, Vidensk. Selsk. Skr. Math, og 

 Naturvid., Afd. (6), V, No. 3, 1890, pp. 252, 318, 378.— Wood-Mason and 

 Alcock, Ann. Mag. Nat. Hist. (6), VII, 1891, p. 270.— Ortmann, Proc. Acad. 

 Nat. Sci. Phila., 1894, p. 191.— Bouvier, Bull. Soc. Entom, France, 1901, 

 pp. 122-123; Conipt. Rend. Acad. Sci., CXXXII, 1901, pp. 643-645.— A. 

 Milne Edwards and Bouvier, Mem. Mus. Comp. Zool., Harvard College, 

 XXVII, No. 2, 1902, pp. 141-159, pis. i-vi.— Hansen, Journ. Linn. Soc. 

 London, Zool., XXIX, 1903, pp. 12-25, pi. iv, figs. 8-9. 



«Bu11. U. S. Fish Comm., XX, Pt. 2, 1902, p. 168. 

 '' See remarks at end of description. 



