ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 387 
Fayette. All of these are west of the Chestnut Ridge. East of the Chestnut Ridge, 
but west of the Alleghany Front, specimens over 80 mm. in length are rare ; only 
one was found at Sand Patch, Somerset County, (86 mm. long). Specimens over 
70 mm. in length are not infrequent here. In the Alleghany Mountain region, 
(between the Alleghany Front and the Blue Ridge) only a few instances of speci- 
mens over 70 mm. in length have been found, and none as large as 80 mm. The 
largest is from MecConnelsburg, Fulton County, 77 mm. East of the Blue Ridge 
(South Mountain) the length 70 mm. is never attained. In the easternmost extrem- 
ity of the state (Northampton and Bucks Counties) even the length of 60 mm. is 
not represented among my material, although I possess large series of specimens 
from this region. ‘Thus it appears that the size gradually decreases from west to 
east. There is hardly any appreciable decrease in size from south to north. The 
smaller number of large individuals from the northwestern section of the state is 
very likely due to the fact that large collections were not made in that part of the 
state. 
Freaks have been observed in several cases. Aberrant forms of the rostrum 
have been repeatedly found, and one variation has been encountered four times in 
which the rostrum has a very slightly developed acumen, so that it is almost evenly 
rounded off anteriorly, with only a small and indistinct median angle or point, 
(female, 25 mm., Schenley Park, Pittsburgh ; female, 50 mm., Templeton, Arm- 
strong County ; male, first form, 64 mm., Branchton, Butler County ; female, 80 mm., 
Monongahela City, Washington County). ‘The rostrum, in these cases, is exception- 
ally short, due to a reduction of the acumen. <A case of an unsymmetrical rostrum, 
with the left angle at the base of the acumen cut off, has also been observed ; this 
is clearly a malformation due to some previous external injury. 
We may class with the freaks a single specimen in which the carapace possesses 
a lateral spine. The specimen is a female (42 mm. long) from Weskit, Armstrong 
County, and it has a small, sharp, lateral spine, but only on the left side of the 
carapace. ‘This is the more remarkable since it demonstrates the importance of this 
specific character. There is not a single other individual among the large material 
at hand which possesses such a spine, although granulations in its place are not 
infrequent. 
Two interesting cases of abnormally developed sexual characteristics have been 
noticed (compare the other cases mentioned under C. (Faxonius) obscwrus). 
1. A large female, 71 mm. long, found March 31, 1905, at Hollidays Cove, Han- 
cock County, W. Va., (Cat. No. 74. 491), which is normal in every respect but one, 
and besides, is undoubtedly sexually normal, since it carried under the abdomen 
