. Decapod Crustacea of Bermuda. Their distribution, variations, and habits. Decapoda (Crustacea). 330 A. E. Verrill—Decapod Crustacea of Bermuda. form, are even less granulated.* Indeed, the latter are scarcely more granulated than the ordinary form of HicorcU. However, the front of *S'. chierea is narrower and more arched than in S. HicorcU ; its lower margin is less sinuous, narrows more toward the ends, and is less turned up at the edge, so that it is less concave above. The orbital notch is not so deep. Still these differences are but slight. The carapace seems to be slightly less convex.
. Decapod Crustacea of Bermuda. Their distribution, variations, and habits. Decapoda (Crustacea). 330 A. E. Verrill—Decapod Crustacea of Bermuda. form, are even less granulated.* Indeed, the latter are scarcely more granulated than the ordinary form of HicorcU. However, the front of *S'. chierea is narrower and more arched than in S. HicorcU ; its lower margin is less sinuous, narrows more toward the ends, and is less turned up at the edge, so that it is less concave above. The orbital notch is not so deep. Still these differences are but slight. The carapace seems to be slightly less convex. The chelae are essentially the same in both, and the carpal joint is roughened in the same way. The merus joints of the pereiopods are about equally flattened in both; the brush of hairs on the under. Figure 8.—Sesarma cinerea (from Florida), slightly enlarged. Phot. A. H. V. side of the last two joints is nearly the same in both, though per- haps a little smaller, and with shorter hairs in iS. cinerea. The differences are so slight that it seems not improbable that S. cinerea is another semiterrestrial race or subspecies that has been derived from /S. HicorcU, under a somewhat different environment. In fact, all those species that live more or less on the dry land or in trees (e. g., S. JRoberti, an arboreal West Indian species) must have been originally derived from amphibious or aquatic species, but the dif- ferentiation has gone farther in some than in others. Doubtless they all go into the sea to breed, and probably they all have similar zoea and megalops larval stages. But in the case of the Bermuda forms, it is easy to believe that they have acquired different breeding habits or different breeding * In Miss Eathbuii's analytical table of Sesarmce (Synopsis American Sesarmae, Proc. Biolog. Soc. Washington, xi, pp. 90, 91, 1897), the smoothness of the suprafrontal lobes, " smooth or nearly so," is made a diagnostic character for S. Eicordi, while S. cinerea i
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