MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 
39 
will extract the following remarks as to its specific character and affinities from the first mono¬ 
grapher of the genus, Dr. Hagen: 
Tlie shape of the rostrum is somewhat analogous to that of C. affinis; the margins are more parallel at the base. 
The lamina of the antenu® is long, but strongly dilated nearer to the tip; the epistoma is shorter and broader than 
in the other species; the basal joint of the inner antenn® has a spine at the tip which in the other species is always 
nearer to the base. The fore border of the cephalothorax is not angulated behind the antenna;, as in all other species. 
Nevertheless the number of the hooked legs, the form of the abdominal legs, and the elongated body and hands, exclude 
C. pellucidus from the other groups.' Some, no doubt, will prefer to regard C. pellucidus as a distinct group or genus, 
still, as I am convinced, without foundation. The most striking differences consist in the aberrations in the shape of 
the foreparts and of the limbs of the head (pp. 33, 34). , . 
Iu speaking of the eyes, Dr. Hagen appears to be in error in stating that the “ optic fibers” ft c * ' ' rt 
are not developed. If reference is here made to the optic nerve, it is, as we shall see further on, ^r',y 2) 
well developed, while, as he truly says, the “ dark-colored pigments ” are not developed. 
The specimens from Wyandotte Cave described by Cope as Orconeetes inermis are scarcely a 
variety of G. pellucidus, as originally stated by us in our paper “ On the Cave Fauna of Indiana,”* 
Professor Faxon also remarks: 
0. pellucidus is subject to considerable variation. In some specimens the rostrum is shorter than in typical 
specimens, and contracts more from the base to the lateral teeth, which are much less prominent. The spines of the 
postorbital ridge and sides of the carapace are slightly developed. This is the form described as a new species 
(Orconecfes inermis ) from Wyandotte Cave, Indiana, by Professor Cope, in 1872. I owe to Prof. A. S. Packard an oppor¬ 
tunity to examine Cope’s type. It is a male, Form II, with the first pair of abdominal appendages not articulated, a 
condition often found in the second form males of this species. After an examination of this specimen I can indorse 
the opinion of Hagen (Amer. Naturalist, Aug., 1872), aud Packard (Fifth Ann. Kep. Peab. Acad. Sci. for 1872), ex¬ 
pressed before seeing the specimen, that the variation is not of specific value. All the specimens which I have seen 
from the Indiana caves, amounting to six in number, belong to this form. But the same form also comes from the 
Mammoth and neighboring caves in Kentucky. In a gigantic female in the Museum of Comparative Zoology (No. 
3417, collected in Mammoth Cave by F. W. Putnam) the peculiarities of Cope’s form are intensified. The point of 
the rostrum does not reach the distal end of the peduncle of the antennule, and hardly attains the proximal end of 
the distal segment of the peduncle of the antenna.t The lateral rostral spines are reduced to salient angles. The 
postorbital ridges are destitute of spines, as in C. bartonii. The antennal scales reach but to the proximal end of the 
terminal segment of the peduncle of the antenna. The lateral spinules of the carapace are represented by granular 
tubercles. The spines of the meros of the cheliped are short and tooth-like, those on the upper surface are blunt, 
those beneath are irregularly disposed, without the clear biserial order seen in the typical form, and also in Cope’s 
type of 0. inermis. The hands are broad, flattened, and tuberculate. 
This species is more widely diffused throughout the cavernous region of Kentucky and Indiana 
than is generally supposed. 
A male collected by us from Bradford Cave, Indiana, does not differ from a male from Mam¬ 
moth Cave. 
In a male from one of the Indiana caves (which cave is not indicated) the cephalothoracic 
suture is much more acutely produced posteriorly than in a male from Mammoth Cave. 
In the male the rostrum is narrower and its spines, both frontal and lateral, are longer and 
slenderer than in the female. 
Comparing two males of the same form from Mammoth and Wyandotte caves, the former has 
the right hand the larger, and the Wyandotte one the left hand the larger. Although the Wyan¬ 
dotte male is a little the smaller, the large hand is about one-fourth larger and is broader than in the 
Mammoth Cave one. The rostrum of the Mammoth Cave example is broader and the sides less raised 
and thickened. In the Mammoth Cave specimen the inner edge of the end of the antennal scale • 
reaches as far as the lateral spines of the rostrum; in the Wyandotte male the scale reaches far be¬ 
yond the lateral spines, more than half way between the lateral spine aud the end of the median spine. 
These I regard as simply individual differences, as in another male from Wyandotte or Bradford Cave 
the large hand is of the same relative size and on the same side as the Mammoth Cave male. 
In the females from different caves in Indiana (received from Dr. John Sloan), one has a slightly 
narrower rostrum than the other, which is a larger individual. 
In a female from Diamond Cave, which we collected, the larger hand is the left one, the rostrum 
aud antennal scale are shorter than in a large female from Mammoth Cave; otherwise it does not 
differ essentially. 
* Fifth Kep. Peab. Acad. Sci., Salem, 94, 1873. 
t In the typical form of 0. pellucidus the rostrum equals or exceeds in length the peduncle of the antenna. 
