ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 355 
Annulus ventralis of female transversely rhombiform, with a short transverse 
groove slightly posterior to the middle, and an S-shaped longitudinal fissure. An- 
terior to the central groove there is on each side of the fissure a strong, tubereuli- 
form elevation, so that the fissure is situated in a rather deep depression. Posterior 
to the central groove, there is a slight elevation, over which the fissure passes. The 
annulus, consequently, appears trituberculate, the two anterior tubercles being 
stronger than the posterior. In young females, the tubercles are only slightly de- 
veloped, and generally the posterior tubercle is almost obsolete. 
Size. — Rafinesque gives as total length 3-9 inches. The maximum, 9 in., = 229 
mm., seems rather strange, since no such specimens have ever been subsequently 
seen, even if we infer that Rafinesque intended the whole length, including 
the claws. Hagen (1870, pl. 5) figures a very large female, which, including the 
outstretched claws, would not be longer than about 7 inches (178 mm.). Its body 
from the tip of the rostrum to the end of the telson, is 132 mm. long. The maxi- 
mum length given by Hagen in the text (p. 61) is 4.7 in, =119 mm; thus this 
figure, although said to be of natural size, is apparently somewhat enlarged. 
The largest specimens ever seen by the writer are in the museum of Oberlin 
College from the Potomac River, a female measuring 120 mm., and a male of the 
first form measuring 105 mm. ‘The largest specimen from Pennsylvania I possess, 
is a female from the Delaware River at Torresdale, and measures 93 mm. in length; 
the largest male (first form) is from the Delaware at Penns Manor, measuring 75 
mm. in length. A male of the second form from Holmesburg is 85 mm. long. 
Specimens over 100 mm. long, mentioned by the writer, (1899, p. 1210), as from 
Philadelphia, are from the New Jersey side of the river, near Camden. 
Colors. —(Plate B, Fig. 3.) An account of the color of this species has been given 
by Faxon (1885a, p. 88). It runs thus: “ Upper surface greenish, mottled with 
darker green, especially on the chelz; tips of fingers orange, preceded by a dark 
green ring, which runs along the outer border of the hand to the wrists; abdominal 
somites ornamented with interrupted transverse chestnut-colored double bands. 
Under surface of a lighter hue.” 
I have repeatedly made notes from live specimens, and have found that the 
shades of color vary greatly, although the general pattern has been correctly 
described by Faxon. The general color of the body may be described as olive-green 
(Ridgway, 1*86, X, 18)°, but it varies toward tawny-olive (III, 17), and olive-yellow 
(VI, 16). he sides of the carapace are generally lighter, of a whitish green. 
In the description of colors, I have used here (and in the following species) the nomenclature of Ridgway (1886), 
and the Roman and Arabic numerals refer to his plates and figures. 
