V. .THE NATADES OF THE GREEN RIVER DRAINAGE 
INGIGENTUCKY: 
By ARNOLD E. ORTMANN. 
(PLATE VIII, MAp.) 
A number of years ago I pointed out (Ortmann, 1913,' pp. 305, 
308-310, 382), that the southern tributaries of the Ohio from West 
Virginia as far as the Licking River in Kentucky possess a Naiad- 
fauna, containing only such types as are found in other parts of the 
Ohio-drainage, and that forms, which show exclusive affinities to the 
Cumberlandian fauna (Ortmann, 1924, p. 40 et seq.; 1925, p. 364 et seq.) 
are absent, although there are many species of wide distribution, 
which belong to both regions. 
Farther westward, the rivers of the state of Kentucky were poorly 
known at the time I first wrote, but in view of the fact, that the 
Cumberland River, containing many true Cumberlandian types ( Cf. 
Wilson and Clark, 1914) belongs to this group of rivers, is also a 
tributary of the Ohio, it became desirable to ascertain the character 
of the faunez of the intervening rivers, and discover whether they are 
intermediate or transitional between the Ohioan and the Cumberlandian 
type, or whether there is here, somewhere, a sharp line separating these 
two faune. 
As for the Kentucky River, the question of the general character 
of the fauna has been solved by Danglade (1922). He enumerates 
forty forms? (/. c. p. 5). All of the forty are well known as belonging 
to the Ohio system (many of them also to the Cumberland and 
Tennessee), with the possible exception of one species: Alasmidonta 
minor (Lea). I have previously pointed this out (Ortmann, 1925, 
p. 344), regarding this as a Cumberlandian species, which had invaded 
the upper Kentucky drainage. I now have changed my opinion, and 
believe that A. minor is an absolute synonym of A. calceolus (Lea), a 
1 The references in parentheses refer to the titles given in the Bibliography at 
the end of this paper. 
* The list given by Danglade evidently is not quite complete, since the lower 
reaches of the Kentucky are still poorly known. 
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