54 Notes on North, Amerioan Crustacea. 



exterior side longest. Chelipeds very unequal in size ; larger one 

 robust ; apex of carpus obtuse or truncate, not tooth-like as in allied 

 species. The larger hand is armed with a tooth or lobe within at the 

 base of the superior edge, and on the inner surface, near the insertion of 

 the dactylus, there is an oval, obliquely-striated area, on which the striae 

 are sharp and parallel, exactly resembling those of a file. In the 

 smaller hand, the corresponding area is covered with utriculiform 

 granules. Ambulatory feet smooth and glossy ; the last two joints only 

 being hairy. Abdomen as in the allied species. Color of preserved 

 specimen, reddish, mottled or banded. Dimensionsof carap. in 5: length, 

 1'2 ; greatest breadth, at the penult antero-lateral tooth, 1-7 inch. 



This species has ranch resemblance to M. mercenaria in 

 general appearance, but is easily distinguished by the smaller 

 number of frontal teeth, and the striated area on the greater 

 hand. 



It was found at Panama by J. H. Sternbergh, Esq. 



Panopeus. 



The genus Pano^peus seems to be in some degree intermediate 

 between Xantho and Pilumnus. In our common species, P. 

 Herbstii, there is a well-marked groove on the palate, indi- 

 cating the efferent passage, although this is not defined by a 

 sharply elevated ridge. The genus is peculiar to America. 

 Certain East Indian forms which have been referred to it, 

 prove upon examination to be generically distinct, and form a 

 separate group, for which I have proposed the name Hetero- 

 panope. 



The genus now contains ten species ; — P. crenatus^ M.-Edw. 

 et Lucas, P. Icevis, Dana, P. chilensis, M.-E. et L., from the 

 western coasts of South America ; and P. herhstii, M.-Edw., 

 P. texanus, Stm., P .^wurdemmini, Gibbes, P. harrisii, Stm., 

 P. ocGidentalis, De Saussure, P. serratus^ Des., and P. ameri- 

 canus, Des., from the eastern coasts of the United States, and 

 the Antilles. 



