%9i!'''] PROCEEDINGS OF THE NATIONAL MUSEUM. 359 



lobes of nearly equal prominence, giving the anterolateral border more 

 the appearance of being flve-tootheJ. The inner suborbital angle is 

 much sharper in this variety. In var. G the carapace is more convex, 

 the front is less produced, and the contour has a more evenly rounded 

 appearance. In var. B the carapace has a more uneven appearance, 

 the punctures and markings are deeper and coarser. The other char- 

 acters are variable aud cross and recross the convenient division made 

 on the basis of the teeth. As a rule, var. G is proportionately broader 

 than var. B while the latter is more hairy. In var. G the color does 

 not extend quite so far upon the hand, and runs from a black to a 

 brown, while in var. B it runs from a black to a liver color. It is 

 worthy of notice that in some specimens from the West Indies and 

 Brazil the color of the fingers is more or less restricted. In var. B 

 the tooth on the large hand at the base of the movable fluger is larger 

 and more conspicuous than in var. G. In no instance is there a 

 groove on the carpus next the articulation with the hand. 



We have a great many specimens from Port Royal Island, South 

 Carolina, taken in the banks near high tide mark. The burrows or 

 holes in which these crabs were concealed did not as a rule contain 

 water, while the specimens of limostis, taken at the same time, were in 

 burrows partly filled with water. These specimens of herbstii are of 

 the var. G or obesus type. The chelipeds are spotted with claret 

 brown, and crossed by irregular lines, giving them a reticulate appear- 

 ance (PI. XXIII, fig. 11). The chelipeds are more slender tiian those of 

 the sharp-toothed or B type (PI. xxiii, fig. 10), which were found on 

 Morgan River, Jericho Creek, and other places at low tide on bunches 

 of oysters. The conclusion reached from the study of the collections 

 from South Carolina is that the varying habit of this crab accounts for 

 its wide diflerentiation in form. Those living ia burrows are the obesus 

 type, while the sharper-toothed forms are dredged or found in low 

 water in various hiding places. From our present knowledge, how- 

 ever, we see no way of dividing the species, as our collections show 

 every intermediate gradation. 



Panopeus herbstii belongs to the section of the genus in which the 

 seventh segment of the sternum in the male is but slightly exposed, 

 and leaves a wide open passage for the verges. Proximal end of sec- 

 ond segment much the broader. The fifth pair of feet border broadly 

 on the third abdominal segment. In the anchylosed segment the sides 

 of the third normal segment are nearly straight, slightly swollen in 

 the center. Sides of the fourth normal slightly concave. Proximal 

 end of the fifth normal the broader, sides nearly straight. Penulti- 

 mate segment with straight and parallel sides. Terminal segment 

 rounded. General outline of last three normal segments not concave 

 but parallel. 



Length of carapace in largest specimen, 40 millimetres ; width, 62 

 millimetres. 



