ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA Srile 
The annulus ventralis of the female has the general shape of that of C. propin- 
quus, but the depression in the middle is well marked, and the anterior part has 
two distinct, subconical tubercles. The posterior part is also elevated into a flat 
and low tubercle. ‘These tubercles are less distinct in young specimens, but always 
well developed in females of medium and large size. 
Size. — Hagen gives the length as 3.5in.=89 mm. The largest individual at 
hand is a female from Pucketta Creek, Allegheny County (Atkinson coll.), which 
measures 93 mm. in length. The largest male of the first form is from the Ohio 
River at Neville Island, Allegheny Co., which is 86 mm. in length. Individuals 
over 80 mm. in length are not rare in the larger rivers. 
Colors (Plate A, Figs. 1 and 2).—The colors of this species are identical with those 
of C. propinquus. In fresh specimens the general ground color is light olive-green 
(Ridgway, 1886, X, 18), with darker spots in young specimens ; in older individuals 
it is rather tawny-olive (III, 17). On the branchial region there is an oblique band of 
eream-color (VI, 20), edged by olive-green near the margin of the carapace, which is 
again cream-color. This cream-color in very brightly colored specimens sometimes 
becomes primrose-yellow (V1, 13). On the anterior margin of the carapace below the 
eyes there isa spot which may be rufous (II, 7), ochraceous-rufous (V, 5), edged with 
sulphur-yellow (V1, 14), ochre-yellow (V, 9), or primrose-yellow (VI, 13). The abdomen 
is olive-green or tawny-olive, shading into chestnut (LV, 9) on the anterior margins of 
the segments. There are one (sometimes two) median and two lateral rows of dark 
olive-green patches. The chele are light olive-green, shading distally into olive-yellow 
(VI, 16). The finger-tips are orange-buff (VI, 22), orange (VI, 3), or raw sienna 
(V, 2), followed by a pale, and a dark green, sometimes almost black band. The 
latter is not always present. ‘The upper surface of the hand at the base of the dac- 
tylopodite has two (rarely one) rufous or ochraceous-rufous (V, 5) articular tubercles. 
The tubercles of the hand are buff-yellow (VI, 19) or buff (V, 15). The articular 
membranes of the hand are wine-purple (VIII, 15). The legs are olive-yellow (VI, 
16) and whitish, with olive-green on upper edges. 
The above colors fade in old specimens, and are often obscured by blackish or 
brownish coats of dirt. A variety with the chele and anterior parts of the carapace 
of a pale dirty bluish color was repeatedly observed in the Alleghany River at 
Sandy Creek and Twelve Mile Island, but only old specimens of this form were 
found. Young specimens generally vary more toward green, old ones toward tawny 
or brown. 
The color of the newly laid eggs ranges from sage-green (X, 15) to dark olive- 
green (X, 18), or often to almost black. When somewhat advanced in development, 
