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IOWA ACADEMY OF SCIENCE 



Vol. XXVI. 1919 



associated with the water which disappears near the quarry, as the 

 tih of the strata of rock would send the water in the opposite direc- 

 tion. The east hranch of Dry Run does not dry up so readily and 

 often continues upon the surface well into the summer. A study of 

 this stream would prove profitable to see whether or not the species 

 found are identical with those in the west branch. The fact that it 

 maintains a connection with the river through a greater period of 

 time would lead one to expect a more varied list of fish inhabitants. 



Pig. 25. — "The Springs" approximately two miles from uppermost quarry 

 and sink hole. This water is not the same as that entering the sink holes. 



The species of fish found in the stretch from the sink holes to the 

 north end of the Diagonal include all forms found in the stream. 

 This is probably due to the great variation in the type of bottom and 

 consequent variation in food supply. Campostoma, Semotilus and 

 the two species of Pimephalcs are found universally, while Boleo- 

 soma and Notropis are limited to regions possessing a gravelly bot- 

 tom for the most part. Of these latter two species, Boleosoma is 

 the more restricted in range. It was found near the lower extremity 

 just above and below the sink holes. \'ery often pools which drie^l 

 up left specimens of Boleosoma stranded. These pools furnish an 

 excellent place for collecting minnows and crayfish for bait and fig- 



