434 BULLETIN OF THE BUREAU OF FISHERIES. 



Callinectes ornatus is by no means rare in Beaufort Harbor though full grown individuals are not to 

 be found. Specimens 3 inches and less in width can usually be collected about Bird Shoal and may 

 easily be distinguished from the commoner C. sapidus by their more brilliant coloration and by their 

 greater pugnacity. It also seems that their claws are stronger than those of C. sapidus of the same size 

 and their nip is correspondingly more painful. 



Genus AREN.a;US Dana. 



ArentEus Dana, iSsi, p. 130. 



Arenaeus cribrarius (Lamarck). PI. xxxiv, fig. 3. 



Porlunus cribrarius Lamarck, 1818, p. 259. 

 Lupa maculata Say, iSrS, p. 445. 



Arenaeus cribrarius Dana, 1852, p. 290; Coucs, 1871, p. 121: Kingsley, 1878, p. 320; Rathbun, 1901, p. 50: S umn er, 1911, 

 p. 672: Fowler, 1912, p. 413. 



Carapace more than twice as wide as long, very finely granidate; produced on each side into a 

 strong spine between which and the orbit are eight strong, somewhat acuminate teeth heavily ciliate 

 beneath; front narrow, not so far advanced as the outer orbital angles, and with three teeth on each side 

 of the median notch; of tliese teeth the outer one forms the inner angle of the orbit and the central one 

 is partly coalesced with the innermost one; superior wall of orbit with two deep fissures dividing it into 

 three lobes; inferior wall of orbit with a wide external fissue and with the inner angle much advanced; 

 lower surface of carapace hairy. 



Chelipeds of moderate size; meros with three spines on the anterior border and a short tuberculi- 

 form one near the distal end of the posterior border; carpus with two spines; hand short, with five longi- 

 tudinal granulose carinae and two spines, one at the articulation with the carpus and the other above 

 the base of the dactyl. Walking legs rather short and weak, densely ciliate. Swimming feet stout. 

 Basal segment of abdomen produced on each side into a strong, sharp, slightly upcurved spine. 



Length of carapace, 27 mm.; width, 59 mm. 



Color, light vinaceous brown or olive brown thickly covered over the dorsal svirface with small, 

 rounded, white spots; tips of walking legs, yellow. 



So far as is known this crab seldom if ever enters the harbor and is rarely washed ashore along the 

 outer beaches. It lives in rather shallow water close to the shore but is sufHciently adroit as a ^vimmer 

 to escape the dangers of the tumbling surf. The collector in search of specimens should be able to haul 

 a seine or an otter trawl about half a mile offshore and parallel with the beach. 



Family CANCRIDAE. 



Brachyrnyncna having the body broadly oval or hexagonal, the last pair of legs 

 not adapted for swimming, the first pair of antennae folding lengthwise, and the second 

 antennas with short, naked flagella. 



This, the typical family of crabs, has been restricted until it now contains but two 

 genera. Of these, one is represented within our limits. 



Genus CANCER Linnsus. 



Cancer Linnseus, 1758, p. 625; restricted by Leach, 1815, p. 308, 320. 



KEY TO THE SPECIES OF THE BEAin^GRT REGION. 



a. Anterolateral teeth of carapace with denticulate margins borealis. 



aa. Anterolateral teeth with the margins granulate irroratus. 



Cancer borealis Stimpson. Northern crab, Jonah crab. PI. xxxv, fig. 2. 



Cancer irroratus Say, 1S17 (pt.), p. 60; Gould, 1841, p. 322. 

 Platycarcinus irroratus Gibbes, 1850, p. 176. 



Concer 6DrC(i/« Stimpson, 1859, p. 50; Kingsley. 18S4, p. 317; R. Rathbun, 1884, p. 769; Sumner, 1911, p. 672; Fowler, 

 1912, p. 133. 



Carapace transversely oblong oval, about two-thirds as long as wide, angular at the sides, the sur- 

 face finely granulate; anterolateral margins divided into nine quadrangular, crenate lobes or teeth, the 



