DECAPOD CRUSTACEANS OP THE BEAUFORT, N. C, REGION. 399 



Genus SCYLLARUS Fabricius. 



Scyliarus Fabricius. 1875, p. 413, 

 Arclus Dana, 1852. p. 516. 



Scyliarus americanus (Smith). PI. xxvni, fig. 2. 



Ardus americanus Smith, 1869, ser. 2, p. 119. 

 Scyliarus {Ardus) gundlachi von Martens, 1872, p. 123. 

 Scyliarus americanus Rathbun. 1901, p. 97. 



Integument rugose and hard except for the membranous tips of the uropods and telson. Carapace 

 as long as the first five abdominal segments, its greatest breadth slightly exceeding its length. Dorsal 

 surface with three longittidinal ridges, the median of which has three bltmt prominences while the lat- 

 eral ones are conspicuously broken toward their anterior ends. Margins of carapace more or less 

 dentate and produced anteriorly into a prominent angle which is continued across the front below the 

 orbits so that the latter appear to be excavated in the dorsal stirface. Abdomen convex dorsally, 

 rugose; each segment slightly notched on the posterior margin and with a conspicuous impressed line 

 running from near the middle line to the pleural angle. Proximal portion of telson and uropods 

 indtirated, the distal half membranous and smoothly rounded. Eyes subspherical, prominent. Anten- 

 nules biflagellate. Antenna of four articles, of which the second and fourth are broad thin scales, the 

 anterior margin of the foiu-th being deeply scalloped. Legs rather small, all simple in the male, fifth 

 pair minutely chelate in the female. Swimmerets of first segment wanting, those of second segment 

 slender and biramous, the others consisting of a single foliaceous branch . 



Two specimens of this animal were dredged by the Fish Hawk in deep water off Beaufort Inlet. 

 The larger of the two measures 39 mm. from the tip of the antenna to the end of the telson. 



Section ASTACURA. 



Reptantia having the abdomen extended, well developed, symmetrical, and well 

 armored, the cephalothorax subcyhndrical, the carapace free from the epistome, the 

 first three pairs of legs chelate, the first pair much stronger than the rest, the rostrum 

 well developed, and the gills numerous. 



Two of the three families which constitute this section are described here. 



Family HOMARIDAE ( = NEPHROPSIDAE of most authors). 



Marine Astacura having the last thoracic segment consolidated with the one in 

 front of it, the pleurobranchs four in number, and with sexual appendages present in 

 the male. 



Nine genera are now recognized in this family. Of these only one is, or was for- 

 merly, represented in the Beaufort region. 



Genus HOMARUS Weber. The lobsters. 



Homarus Weber. 1795, p. 94: Milne-Edwards, H., 1837, t. II, p. 333. 



Homarus americanus H. Milne-Edwards. American lobster. PI. xxviii, fig. 7. 



Homarus americanus H. Milne-Edwards. 1837. t. n, p. 334: De Kay, 1844, p. 23; Coues, 1871, p. 124: Kingsley, 1878-79, 

 p. 320; R. Rathbun, 1885, p. 781; Herrick, 1895, p. 1-252; Fowler, 1912, pp. 96-99: Sumner, 1911, p. 665. 



Cephalothorax subcylindrical, the carapace smooth and punctate above and on the sides, but with 

 short and acute post orbital, post antennal, and infraorbital spines. Rostrum narrow, decurved until 

 near the tip, which is usually more or less upcurved; margins above with 2 or 3 teeth on each side, 

 lower stxrface with from i to 3 teeth a short distance behind the tip. Abdomen strong, its pleura more 

 or less acuminate and directed backward; telson with a spiniform tooth on each side near the tip; 

 basal article of appendages of sixth segment ivith two strong denticles. Antennal scale small; antennal 



