100 A REVISION OF THE ASTACIDA. 
much less developed in the females and second-form males than in first- 
form males. In some, especially young, specimens slight ante-apical teeth 
are present on the rostrum. 
I am indebted to Mr. C. L. Herrick for three examples, two first-form 
males and one female, of his C. seguifer. It does not differ specifically from 
Hagen’s ©. immunis. The antennal scale is a little broader than in the types 
from Illinois, and the anterior process of the epistoma is not so clearly trun- 
cated ; the punctation of the carapace is more pronounced. These differ- 
ences are no greater than we often find in the same species when specimens 
from widely separated localities are compared. The color, as given by Her-. 
rick, is “reddish (crimson) brown, not obviously figured ; tail lighter; fin 
chestnut, marked with gray; chele bright crimson below; there are green 
markings on the body and legs, and some yellow below.” In the female, 
the “abdomen is marked with chestnut bars on each segment above.” “The 
young males have the chele greenish blue and mottled, while the coloration 
of the body is like the females.” The figure of the antennal scale (fig. 7, b) 
in Herrick’s paper is very incorrect. 
The hand of this species figured by Hagen on Plate VIII. of his Mono- 
graph is not of the normal form, but belongs to the specimen from Hunts- 
ville, Ala., mentioned on page 72. Although this specimen is a first-form 
male, the tufts of cilia on the second pair of legs are hardly developed. 
The female from Beaufort, N. C., (M. C. Z., No. 3356,) doubtfully assigned 
to this species by Hagen, does not belong here. It is perhaps C. Diogenes. 
I have seen a few specimens of C. imnumis with the internal margin of 
the movable finger straight, without the excision at the base, but such cases 
are very rare. 
In the typical form of C. dmmunis the margins of the rostrum are sinu- 
ate at the apex, without spines at the base of the acumen. In many of the 
well-grown second-form males and females from the Detroit River, small 
lateral spines are developed at the base of the acumen; and these speci- 
mens thus lead to a form from Obion Co., Tenn., (Coll. U. S. Nat. Mus.,) in 
which the lateral rostral spines are developed in all the examples exam- 
ined (seven second-form males, nine females). The sides of the rostrum 
in some of these are nearly parallel as far as the lateral spines. Although 
these specimens are of moderate size, they show the marks of immaturity, 
the chelipeds being small, the chelee narrow, with slender fingers. The inner 
finger is generally excised at the base, as in the typical form; the lateral 
