88 A REVISION OF THE ASTACIDA. 
from Red Bank, N.J., Dr. Jos. Leidy, labelled “A. affinis ( fide L. R. Gibbes).” 
Gibbes states that his own specimens came from Florida. They probably 
belonged to some other species. Hagen states that Gibbes’s types of A. Bar- 
owt in the Academy of Natural Sciences of Philadelphia are C. afinis, but 
they are in fact C. placidus Hagen (Nos. 126*, 126°).* 
Types, male and female, of Girard’s C. affns, from Reading, Pa., collected 
by Professor Baird, were communicated to Dr. Hagen by Dr. Stimpson. The 
male belonged to the second form; the specimens were young, with only one 
lateral thoracic spine. I have myself discovered in the collection of the 
Smithsonian Institution four types (two males, two females) of Cambarus 
Pealei Girard (Smithson. Cat. No. 2081), from the Potomac River, Washing- 
ton. The largest is 4} in. in length, the smallest 54 in. They are the 
adult C. afiius Say. These are the only types of Girard’s Cambari now in 
existence, as far as I can discover. The rest were probably burned when 
loaned to Stimpson, in the great fire of Chicago. 
Color.— Upper surface greenish, mottled with darker green, especially 
on the chele; 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. In recent alcoholic specimens the 
bands of the abdomen turn bright blood-red. 
In some specimens the basal segment of the telson has three spines on 
each side of its posterior margin. 
The centre of distribution of C. afinis appears to be the great rivers 
which empty into the Delaware and Chesapeake Bays. 
According to Dr. C. C. Abbott (American Naturalist, VII. 80, 81), “Cam- 
barus ufinis is apparently the river species at Trenton, N. J. We have been 
able to find it, as yet, only in the Delaware River, usually frequenting 
the rocky bed, but also, in fewer numbers, on the mud-bottomed portions 
of the river. They are usually found resting under flat stones, well out 
from the banks of the stream, where the water is of considerable depth. 
Wherever the vegetation is dense we have failed to find them; nor have 
we seen anything to indicate that it is a burrowing species.” 
Since this was written, Dr. Abbott and myself have taken C. affnis in 
great numbers from shallow ditches in the Delaware meadows near Trenton, 
N.J., in company with C. Blandingii. 
* Seep, lid: 
