684 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



extremity. The terminal segment of the body has the middle portion 

 of the posterior extremity regularly rounded, the post-lateral angles 

 not extending quite as far as the middle portion. The basal segment 

 or peduncle of the uropoda is short, being only 1 mm. in length 

 from the tip of the middle part of the abdomen. The branches are 

 equal in length, and are twice as long as the peduncle. The inner 

 branch is furnished with one short bristle about 1 mm. in length. 

 The legs are all ambulatory. 



LIGYDA OCEANICA (Linnaeus). 



Oniscus oceanicus LINNAEUS, Syst. Nat., 12th ed., I, Pt. 2, 1767, p. 1061. 

 Cymothoa oceanica FABRICIUS, Mantissa Insectorum, I, 1787, p. 242. 

 Ligia oceanica FABRICIUS, Suppl. Ent. Syst., 1798, p. 301. BREHISSON, Mm. 

 Soc. Linn. Calv., 1825, p. 258. 



FIG. 728. LIGYDA OCEANICA (AFTER SARS). a, ANTERIOR LIP. 6, FIRST ANTENNA, c, HEAD 



(VENTRAL VIEW), d, TIP OF MANDIBLE, e, SECOND ANTENNA. /, POSTERIOR LIP. Q, MANDIBLE. 



h, FIRST MAXILLA, i, DORSAL VIEW OF FEMALE, j, TIP OF MANDIBLE, k, MANDIBLES. I, MAX- 

 ILLIPED. m, SECOND MAXILLA, n, SEVENTH LEG. o, FIRST LEG. p, SECOND PLEOPOD OF FEMALE. 

 q, FIRST PEOPOD OF MALE, r, ONE BRANCH OF TJROPODA. s, FIRST PLEOPOD OF FEMALE, t, SEV- 

 ENTH LEO (TIP), u, UROPOD. v, ABDOMEN (VENTRAL VIEW), w, SECOND PLEOPOD OF MALE. 



X, THIKI) 1'I.KOI'OD OF FEMALE. 



