40 Proceedings of the Biological Society of Washington. 



disappear. In June and September, 1914, the junior autlior 

 thoroughly seined a section of Little Seneca and Tenmile creeks, 

 near Boyds, Maryland. These are branches of Seneca Creek, 

 which empties into the Potomac River at Rushville. 



Because of the proximity of the Seneca basin to the streams 

 about Washington, D. C, the present paper may be of interest 

 to those interested in the distribution of the species of this 

 region. The list contains 34 species from the vicinity of Rush- 

 ville, all but one being from the canal, and 19 species from 

 Little Seneca and Tenmile creeks. Of the 41 species listed, 12 

 were common to the two regions, as follows : 



Schilbeodes insignis Notropis photogenis amoenus 



Catostomus commersonii Hybopsis kentuckiensis 



Hypentelium nigricans Anguilla rostrata 



Semotilus atromaculatus Lepomis auritus 



Pimephales notatus Micropterus dolomieu 



Notropis analostanus Boleosoma olmstedi 



The following species were found only in Little Seneca and 

 Tenmile creeks : 



Semotilus corporalis Rhinichthys atronasus 



Notropis cornutiis Exoglossum maxillingua 



Rhinichthys cataractse Etheostoma flabellare 



Uranidea gracilis 



Without exception, these species are characteristic of the 

 smaller streams, usually inhabiting the swifter creeks and 

 brooks. 



McAteeand Weed (Proc. Biol. Soc. Washington, Vol. XXVIII, 

 1915, p. 6) list 27 species from the Chesapeake ahd Ohio canal 

 between locks 11 and 12. Of these, all but four were taken in 

 the section seined near Rushville and eleven additional species, 

 as follows : 



Ictalurus furcatiis Notropis procne 



Moxostoma macrolepidotum Notropis analostanus 



Carassius auratus Hybopsis kentuckiensis 



Hybognathus nuchalis Fundulus diaphanus 



Pimephales notatus Percopsis omiscomaycus 



Micropterus salmoides 



Of these, Moxostoma macrolepidotum was very abundant and 

 Hybognathus nuchalis and Pimethales notatus were common. 



