ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 435 
main features of this drainage, which differs so strikingly from that which exists 
to-day. 
The easternmost of these rivers was the Spencer River, or Old Monongahela, or 
Old Upper Ohio, which drained southwestern Pennsylvania, northern West Vir- 
ginia, and a small part of eastern Ohio. West of it was the Old Kanawha River, 
or Old Middle Ohio, or Teays River (Leverett, 1902, p. 100, map, p. 101; Tight, 
1903), which drained parts of West Virginia and Kentucky, and the larger part of 
central Ohio. The old Muskingum-Tuscarawas River belonged to this drainage, 
the Muskingum River not flowing southward, but westward and southwestward 
from near Zanesville, Ohio, to Circleville, Ohio, thus joining the Old Kanawha 
(Newark River; Tight, 1903, Pl. 1). 
The divide of the Old Kanawha to the westward was formed by the Cincinnati 
uplift, and was situated according to Leverett (1902, p. 100) near Manchester, Ohio, 
on the present Ohio River. Beyond this divide we have the Lower Ohio system 
(Leverett, p. 109). The Preglacial lines of discharge in this region are rather 
obscure, but according to Leverett and Newsom (1902, p. 168, PI. 6) it is probable 
that a large part of the present system of streams was tributary to the lower Ohio in 
Preglacial times, but that a small number of them may have had a northward dis- 
charge through the Great Miami basin in western Ohio (Leverett, p. 116). There 
are distinct indications of a northward drainage in the vicinity of Cincinnati (Cin- 
cinnati River, Tight, 1903, Pl. 1). This possibility is also admitted by Newsom 
(1902, p. 181). 
We may take it for a well established fact that in Preglacial times at least two 
rivers existed in this region, the Spencer and the Old Kanawha, which did not 
drain into the Ohio and Mississippi in a southwestern direction, but flowed north- 
ward into the Erigan basin. Westward there was very likely a third river (‘Old 
Miami”) running in a similar direction; but in this region we arrive at the old 
Preglacial divide between the Lower Ohio and the Erigan River. It remains 
doubtful whether the latter drained to the St. Lawrence Gulf or to the Mississippi 
by the way of the present Wabash. 
Assuming the theory of the former existence of an Old Miami (or Cincinnati) 
tiver, we see that there are certain interesting relations of these three old rivers tu 
the present distribution of the three forms of Cambarus under discussion. 
Of course, we must disregard those parts of the ranges of these forms which lie 
‘SSee above, p. 429. Descriptions are given by Foshay, 1890, White, 1893, and Leverett, 1902, p. 88 (with map 
on p. 89). Additional evidence has been furnished by Hice, 1903, p. 302. Another name is Pittsburgh River ( Tight, 
1903, Pl. 1). 
