DECAPOD CRUSTACEANS OF THE BEAUFORT, N. C, REGION. 437 



Genus PANOPEUS Milne-Edwards. 



Panopeus H. Milne-Edwards. 1834-1840, t. i, p. 403. 

 Eupanopeus Rathbun, 1898, p. 273. 



Panopeus herbstii H. Milne-Edwards. Common mud crab. PI. xxxiv, fig. g. 



Cancer panope Herbst. iSoi (?). p. 40; Say, 1817, p. 58. 



Panopeus herbsiii H. Milne-Edwards. 1S34, t. i, p. 403; Coues. 1871. p. 120; Kingsley. 1878-79, p. 318: Benedict and 



Rathbun, 1891, p. 358; Sumner, 1911, p. 673. 

 Panopeus herbstii var. obesus S. I. Smith, 1869. p. 278. 

 Eupanopeus herbstii Rathbun, 1898, p. 273: ibid., 1901, p. 28; Verrill, 1908. p. 344; Fowler, 1912. p. 122. 123. 



Carapace about two-thirds as long as wide, regions well marked, surface sparingly granulate; antero- 

 lateral margin with five teeth, of which the first two are coalescent, the third and foiulh are larger, promi- 

 nent, and with arcuate outer margins and acute tips, while the fifth is smaller, acute at the tip and 

 has the outer margin straight ; a transverse ridge extends inward from the fifth tooth and a shallow groove 

 from the fourth tooth; front with a narrow median fissure, the anterior margin of each half sinuate. 



Chelipedsheavj', finely granulate; carpus without a groove on the superior surface and with a blimt 

 internal spine; hands uneqtial and dissimilar, the larger one having the movable finger curved and 

 strongly toothed at base, while the finger of the smaller one is more nearly straight. 



Measurements of a male: Length of carapace, 26 mm; width, 38 mm. 



Color, a dirty gray or slate color; fingers black, the color extending a little onto the palm of the hand. 



One of the most abundant crabs of the region, being foimd wherever the bottom in shallow water 

 is muddy or covered with shells or stones. In suitable localities, along the edges of the higher marshes, 

 it is often found in burrows and frequently associated with Sesarma reticulata and Uca minax. Speci- 

 mens from such localities are usually more convex, smoother, have blunter anterolateral teeth, a less 

 conspicuous tooth at the base of the movable finger of the large hand and are more inclined to be of a 

 purplish color than are specimens taken from the channels of the harbor. They probably represent 

 the variety obestis Smith, which has been recorded from the Beaufort region by Coues and Kingsley. 

 In their paper on the genus Panopeus Dr. Benedict and Dr. Mary J. Rathbun do not recognize the 

 variety obesus as a subspecies, but after a careful study of a large number of specimens it was their con- 

 clusion that the obesus characters, rather than being inherent and transmissable ones, are the result of 

 habitat and habits. 



Genus EURYPANOPEUS A. Milne-Edwards. 



Eurypanopeus A. Milne-Edwards. 1880. p. 318. 



Etirypanopeus depressus (Smith). Flat mud crab. PI. xxxiv, fig. 4. 



Paitopeus depressus Smith, 1869, p. 283: Kingsley, 187S-79, p. 319: Benedict and Rathbun, 1891. p. 336: Paulmier, 1905, 



p. 140; Fowler, 1912, p. 117-118. 

 Eurypanopeus depressus A. Milne-Edwards, 1880, p. 320; Sumner, 1911, p. 673. * 



Carapace about three-foiu'ths as long as wide, flattened posteriorly, convex in the anterior half, 

 minutely pubescentand with several fine transverse rugse; anterolateral teeth three, the first two having 

 coalesced to form a broad lobe whose margin is only slightly sinuate, the remaining teeth acute and 

 thin edged ; front nearly straight, median notch small or wanting altogether. 



Chelipeds dissimilar and very unequal ; the smaller one more rugose than the larger and with the 

 margins of the fingers nearly straight and opposable for a considerable distance while the tips are thin 

 edged and hollowed out — "spoon-shaped"; larger cheliped with nearly smooth articles, the hand very 

 heavy and inflated, movable finger strongly curved, obscurely toothed at the base and meeting the 

 immovable one only at the tip ; in the unworn condition both fingers show indication of the spoonlike 

 flattening. 



Length of carapace, 14 mm.; width, 19.5 mm. 



^Color, mottled grayish olive ; fingers black, the color of the immovable finger extending well onto 

 the palm. 



This species appears to frequent localities where the water is comparatively clean and is not often 

 found where the other mud crabs abound. 



