THE GRAPSOID CRABS OF AMERICA. 



75 



propodi, last dactylus long, equaling the propodus, and slightly 

 curved. 



Descri'ption of male. — Much smaller, diameter of carapace about 

 half that of female, a little longer than wide, harder than female, 

 and with a striking, light color-pattern of bare spots on a dark 

 ground of pubescence, consisting of a median stripe, constricted in 

 the middle and behind, a subtriangular spot each side before the 

 middle and a linear spot each side behind. 



Chelipeds shorter than in female, palms and fingers stouter. Legs 

 wider, especially the propodal segments of the first three legs, the 

 posterior surface of which is overlaid with a thin fringe of hairs 

 attached near upper margin; last leg relatively shorter than in 

 female, not reaching middle of propodus of third; dactylus more 

 nearly like third than in female. 



Abdomen at its middle about one-third width of sternum, grad- 

 ually narrowing from third to seventh segment, sides of third convex, 



Fig. 35. — Pinnotheres maculatcs, male, x 8. 

 (After Smith.) 



Fig. 36. — Pinnotheres 

 maculatus, outer max- 

 illiped of female 

 (36782), X 10. 



seventh obtusely rounded. Sutures between segments of abdomen 

 and sternum marked with a narrow line of dark pubescence. 



Variations. — Young females resemble the male except in the shape 

 of the abdomen and the character of its appendages; they have the 

 coloration, pubescence and long hair on the legs, all male characters. 

 These masculine-looking females are free-swimming like the young 

 and sometimes attain a size of 5.2 mm. long. Normal females, color- 

 less and commensal in habit, are 3.3 mm. (16042) and upward in 

 length. The long hair persists on the legs in medium-sized specimens. 

 Some males, perhaps always commensal individuals, resemble adult 

 females in their consistency and absence of color; such range from 

 4 mm. (14567) long upward. The same is true of some young 

 females, except as to size. 



Individuals vary (1) in the stoutness of the chelae, the lot from 

 Jamaica having very stout chelae, while in that from Louisiana the 



