CRAYFISHES. 385 
always furnished near the tip with a median longitudinal carina. This carina is 
usually well defined and extends from near the acumen backward to about the 
middle of the broad flat surface of the rostrum; it is generally followed by an ill- 
defined and very shallow foveola. In less typical specimens the carina is reduced 
to a very low, rounded, almost invisible elevation just between the lateral angles 
of the rostrum, or in some cases is wanting altogether; in such specimens the 
other characters,— cylindrical carapace and broad, flat rostrum,— will hardly 
be sufficient to separate them from other closely related subspecies. 
“Type, U. 8. Nat. Mus. No. 23,962. Gandy Creek, Osceola, Randolph 
Co., W. Va. W. P. Hay coll., July 12, 1899. Mas, forma secunda. 
“This crayfish is abundant in the main stream as well as in the tributaries 
of the Tygart’s Valley and Cheat Rivers in Randolph County, West Virginia. 
I have collected typical examples from the Tygart’s Valley River at Beverly 
and near Elkins. It is most abundant, however, further east in the Cheat River 
basin, and Osceola may be regarded as approximately the centre of its distribu- 
tion.” — W. P. Hay MS. 
C. b. carinirostris Hay is a slightly differentiated local form of C. bartonii 
found chiefly in the mountain streams of Randolph Co., W. Va., the Cheat and 
Tygart’s Valley Rivers and their tributaries. Outside of Randolph County, Mr. 
Hay secured a few specimens at Albright, Preston Co., at Queens, Upshur Co., 
in the above-named river-basins. It is also probably to be found in the upper 
waters of the Kanawha River basin further to the south, since there are a few 
specimens in the U. 8. National Museum (Nos. 23,975, 28,605) from the West 
Fork of the Greenbrier River, near Durbin, Pocahontas Co., and from Laurel 
Creek, in second Water Cave, near Greenville, Monroe Co., that are pretty char- 
acteristic examples of this race. 
The median carina on the upper surface of the rostrum is a rather elusive 
character, in many individuals it is searcely if at all apparent. Such specimens 
retain, nevertheless the peculiar quadrangular outline of the rostrum, which 
is often a trifle broader at the base of the acumen than it is in the middle. 
The areola is of moderate width and not so thickly pitted as it is in C. b. 
montanus. 
The dimensions of Mr. Hay’s type are as follows:— 
Length, 63 mm.; length of carapace, 32 mm.; length of areola, 117 mm.; 
width of areola, 22 mm.; width of rostrum between the eyes, 4 mm.; length of 
chela, 25 mm.; breadth of chela 117 mm.; length of dactylus, 162 mm. 
