38 CORA D. REEVES. 



until close to the edge of the rapids, he may see the startled fish 

 flee by quick short dashes and sudden turns, and then they dis- 

 appear. By carefully examining the bottom they may now be 

 found lying in sinuous curves on the gravel or nearly hidden un- 

 der the edges of stones with only a small part of the head or tail 

 in sight. Here they pose at any angle to the current. They 

 are often seen peering among the stones for food while supported 

 on the pectoral fins so that the head and front part of the body 

 are lifted above the bottom. The large pectoral fins are used 

 both for progression and in directing movement. The second 

 dorsal is usually elevated and with the anal presents a broad sur- 

 face to the water when the tail is used in swimming. This very 

 likely helps in their rapid, jerky, forward rushes which more 

 resemble the leaps of a cricket than the graceful movements of a 

 fish. The sudden darts and quick turns may serve to confuse an 

 enemy, and to allow the fish to make off. But when no shelter 

 is available the darter assumes a death-like quiet, and is then 

 nearly invisible on the gravel bottom. 



The shyness of the Etheostoma was shown when a number were 

 brought into the laboratory and placed in an aquarium. For 

 weeks they would not eat while observed and when any one was 

 near they lay motionless upon the bottom. In time they learned 

 to come at once to the side of the aquarium when I approached 

 to feed them. But even after six months they fled as though 

 frightened when a stranger came near or when I appeared in 

 light colored clothing to which they were not accustomed. They 

 seem to be capable of as much discrimination as the dace (Wash- 

 burn and Bentley, 1 906), but like young Necturus (Whitman, 1 899) 

 they are extremely timid so that it is a long time before they 

 show their intelligence by their behavior. 



III. The Breeding Colors, Habitat and Behavior. 



With the coming of the breeding season * a change takes place 

 in the rainbow darters as to color, habitat, and activities. As 

 stated, the females retain their usual colors. They are somewhat 



x The breeding this year (1906) was observed from April 24 to June 2. It is 

 probable that the season began before my first records, as the males in the brooks had 

 their bright colors the second week in March. 



