380 MEMOIRS OF THE CARNEGIE MUSEUM 
Size. — This species in western Pennsylvania reaches a considerable size, although 
the maximum recorded by Hagen (3.6 = 91 mm.) has not been observed. Faxon, 
(1885a, p. 64), mentions a specimen from the Mammoth Cave, Ky., measuring 108 
mm., but this is not the typical form. ‘The largest individuals in the Carnegie 
Museum are two females, the one from Braeburn, the other from Derry, Westmore- 
land County, both measuring 87 mm. in length. The largest male (first. form) is 
from North Versailles Township, Allegheny County, and measures 83.5 mm.” In 
western Pennsylvania specimens over 80 mm. are not altogether rare. 
In the eastern portions of the state this species is much smaller. The largest 
specimen at hand is a female from Roxboro, 67 mm. long, and a male (first form) 
from Manayunk, Philadelphia County, 66.5 mm. long, (both collected by H. Gera). 
Specimens over 60 mm. are not frequent in eastern Pennsylvania. 
Colors. —Generally dull and not much varied, greener in young specimens, 
browner in old ones. (See Plate B, Fig. 1.) 
The carapace and abdomen olive-green (Ridgway, 1886, X, 18) to tawny-olive 
(III, 17), chestnut (LV, 9), and burnt wmber (III, 8), a shade darker dorsally, lighter 
on the sides. Margins of rostrum, in the browner specimens, ferrugineous (IV, 10). 
Distal third of finger rwfous (IV, 7), or tawny (V, 1). Tubercles of the cutting edges 
of fingers ochraceous buff (V, 10). In brown individuals there is generally some 
green on the chelee. 
Aside from young individuals, where the normal olive-green prevails, this species 
shows a distinct tendency toward the brown and chestnut shades, more so than the 
river species, C. limosus, C. propinquus, and C. obscurus. 
In some cases the colors are brighter. Individuals shading to a copper-color are 
not rare, and I have seen a few where a dirty slate-blue was the ground-color. Of 
course, as in other species, in old specimens the original colors are largely obscured 
by a deposit of mud, rendering the specimens sometimes almost black. 
In very young specimens (10 to 20 mm. long) the color is olive-green, semitrans- 
parent, with the chelee almost entirely ferrugineous. 
The color of the newly laid eggs is almost black, with, or without, a purplish hue 
(indian-purple, VIII, 6). In a more advanced stage they become particolored : 
prune-purple (VIII, 1) or dahlia-purple (VIII, 2) on one side, grayish or whitish on 
the other. 
The Carnegie Museum possesses seven hundred and fifty-five specimens of this 
species, six hundred and fourteen of which are from the state of Pennsylvania, 
5 The female from Hill, Westmoreland County, mentioned previously (Ortmann, 1905a, p. 391) is 85 mm., not 
89 mm. as stated ; the male from Cheat Riyer (ibid.) is not 92 mm., but 82 mm. in length. 
