456 BULLETIN OF THE BUREAU OF FISHERIES. 



Chelipeds rather long; in the male about as long as body, feeble; fingers sharp-pointed, finely 

 denticulate, and in contact distally. First pair of legs larger than the others; last pair much reduced 

 in size. 



Dimensions of a male: Length, 9.5 mm.; width, 5.8 mm. 



Occasionally found among the hydroids and sponges growing on wharf piles. The carapace and 

 legs are usually covered with such a thick gro\vth of sponge that it is only after tediously removing the 

 foreign objects that the crab can be definitely seen. 



Genus LIBINIA Leach. 



Libinia Leach, 1815, p. 129. 



KEY TO THE SPECIES OP THE BEAUFORT REGION. 



a. Median line of carapace with about six spines dubia. 



aa. Median line of carapace with about nine spines emarginaia. 



Libinia emarginata Leach. Spider crab. PI. xxxviii, fig. 6. 



Libinia emarginata Leach, 1815, p. 130; Smith, 1879, p. 45; Rathbun, 1892, p. 235; Paubnier. 1905. p. 145; Sumner, 1911, 



p. 670; Fowler, 1912, p. 386. 

 Libinia canalic-ulata Say, 1817, p. 77; H. Milne-Edwards, 1834-1840, t. i, p. 300; Gibbes, 1850, p. 169; Coues, 1871, p. 120; 



Kingsley, 1S7S-79, p- 316. 



Carapace orbicular, about one-sixth longer than wide, spinous and tuberculate, and with a dense 

 covering of short hairs. The larger spines are arranged as follows: A median row of about nine, ex- 

 tending from near the base of the rostrum to the posterior border; two subhepatic, of which the anterior 

 is the longer; a lateral row of five; two spines, in addition to the median one, just above the posterior 

 border; and about three on the branchial region; spiniform tubercles are scattered about among the 

 larger ones. Rostrum slightly depressed, emarginate, or bifid at tip; a median groove between the 

 eyes. A deep groove marking off the gastric region. Orbits \vith a prominent preorbital spine, two 

 smaller spines beneath, on the basal article of the antenna, and one fissure above and one beneath. 



Chelipeds equal, larger in the male; hands granulate, fingers smooth, evenly denticulate and about 

 half as long as himd. Ambulatory legs long, hairy, luiarmed, often unequal and asymmetrical — the 

 result, perhaps, of injurj' and subsequent regeneration. 



Color, a brownish or dirty yellow. 



Length of a female, 62 mm.; greatest width, 58 mm. 



Not uncommon in Beaufort Harbor. 



Libinia dubia H. Milne-Edwards. Spider crab. PI. xxxvni, fig. 5. 



Libinia dubia H. Mihie-Edwards, 1834-1840, 1. 1, p. 300; Gibbes, 1850, p. 169; A. Milne-Edwards, iSSo, p. 129; Pautmier, 

 190S, p. 14s: Simmer, 1911, p. 670; Fowler, 1912, p. 114. 



Very similar in general characters to L. emarginaia but with a more pyriform carapace and fewer 

 spines. There are but six spines in the median row; tlie preorbital, subhepatic, and lateral spines are 

 stronger than in L. emarginata, but the spiniform tubercles are few or wanting altogether, and the ros- 

 trum is slightly longer and more definitely bifid. The antero-lateral angle of the buccal frame is spinous 

 in the present species. 



Length of carapace of a male, 85 mm.; width, 75 mm. 



This is the more common species in Beaufort Harbor and can usually be collected when wanted 

 in the shallower water xuider the wharves along the town front. Occasionally large individuals are 

 found on Bird Shoal in pools left by the falling tide ; less frequently a specimen is brought up in the 

 dredge. Immature individuals are often completely overgrown with sponges, hydroids, or ascidians, 

 but the larger ones are usually nearly clean. Neither this nor the preceding species appear to be as 

 abundant at Beaufort as they are farther north. 



Genus MACROCCELOMA Miers. 



Macrocceloma Miers, 1S79, p. 665. 



KEY TO THE SPECIES OF THE BEAUFORT REGION. 



a. Carapace with dorsal spines in addition to the epibranchial and posterior spines camptocerum. 



aa. Carapace without dorsal spines in addition to the epibranchial and posterior spines. . .irispinosum. 



