ORDER DECAP0DA — PANOPEUS. 



GENUS PANOPEUS. Milne-Edwards. 



Many of the characters of the preceding genus. The anterior lateral borders of the shield 

 short. A hiatus on the lower border of the orbits, below the external angle. 



Panopeus herbsti. 



PLATE IX. FIG. 26. 



Cancer panope. Herbst, Versuch einer, etc. pi. 54, fig. 5. 



C. id. Say, Jour. Acad. Nat. Sciences, Vol. 1, p. 58, pi. 4, fig. 3. 



Panopeus herbsti. Milne-Edwards, Hist. Nat. des Crust. Vol. 1, p. 403. 



Description. Shield transversely oval, granulated on the sides ; its surface irregularly fur- 

 rowed, with a subquadrate elevation in the centre, and another posterior to it. Three or four 

 serrate and apparently truncate teeth on the antero-lateral margins : a small tooth at the ex- 

 ternal angle of the orbit, above the notch or hiatus. Anterior feet with minute granulations 

 which disappear with age, large, ventricose, subcompressed, unequal : a small pointed tuber- 

 cle on the inner bordej of the carpus or wrist. Second segment of the abdomen of the male 

 as long as the two adjacent ones. Feet small and smooth. 



Color, blackish brown. Hands yellowish, separated by a denned line from the black 

 finger and thumb. 



Length, 8. Transverse diameter, 1-1. 



This species is commonly known on our shores by the names of Mud Crab and Oyster Crab. 

 It is frequently taken while dredging for oysters, and is almost invariably found on oyster 

 beds. It is also supposed to be injurious to the Oyster, by feeding on the young spawn. It 

 has not yet been observed, as far as I am aware, north of Cape Cod. On the coast of New- 

 York, New-Jersey and Virginia, it is very common. 



Panopeus limosus. 



Cancer limosus. Say, Journ. Acad. Nat. Sciences, Vol. 1, p. 446. 

 Panopeus id. Milne-Edwards, Hist- Nat. Crust. Vol. 1, p. 404. 



Description. Rather smaller than the preceding, which it greatly resembles. Shield granu- 

 lated ; the antero-lateral margin with three serrate teeth, granulated on their edges, and a 

 fourth anterior and scarcely distinct from the canthus of the orbits. A conic tooth below the 

 anterior tooth of the edge of the shield. Anterior feet equal ; carpus with a prominent 

 obtuse spine on the internal surface, but with no angle beneath. Second segment of the 

 abdomen in the male much shorter than the two adjacent ones. 



Color, blackish brown ; feet olive-green ; fingers yellowish white. 



Length, 1-0. Transverse diameter, 1"5, 



This species is also known as the Mud Crab, and appears to have the same geographic 

 range with the preceding. 



