54 CORA D. REEVES. 



area of the bottom surrounding the nest is guarded (Reighard, 

 1903 and 1905) and so may be considered the holding. Thus 

 the habit which the male of Etheostoma shows of guarding a lim- 

 ited area of the bottom may be regarded as more primitive than 

 that of the nest-building fishes. It represents probably a stage 

 in the evolution of the nest-building habit. 



2. Displays of Color and of Movement. 

 There is a marked difference in the behavior of the males and 

 females on the breeding area. The females are passive and, save 

 as they swim off to avoid the males that crowd about them to 

 stimulate them with their vibratory tapping, they make no re- 

 sponse to the solicitation of the male, no displays of color and no 

 responsive movements. Only once have I seen a female respond 

 by a trembling movement of the head and pectoral fins. In all 

 other cases the females appeared indifferent to the fish about 

 them. In contrast to this is the behavior of the males. The 

 large, brilliant males make less use of mechanical stimulation 

 than do the smaller ones. As has been stated the larger males 

 sometimes remain quiet at the side of the female for a consid- 

 erable time while only a few inches distant and in full view. Oc- 

 casionally one places himself at right angles to a female and, with 

 his head about an inch from her's, elevates his gill covers and 

 vibrates his pectoral fins. Whether either of these attitudes is 

 for the purpose of displaying to the female the colors of the 

 male is not easily determined. The younger, less brilliant males 

 have never been observed to make any display of color and ap- 

 pear to rely wholly upon mechanical stimulation. They are 

 more active than the older males and follow the females more 

 persistently so that the vigor of movement shown by the males in 

 courting may be said to vary inversely witn the brilliancy of their 

 colors. The rate of the vibratory movement of the head of the 

 male has not been measured but was compared with the rate of 

 the most rapid tapping which could be made by a slight movement 

 of the fingers and was then estimated at from four to eight per 

 second. As the lateral line organs are sensitive to such vibra- 

 tions (Parker, 1903) it is possible that when the fish are not in 

 contact the vibratory movements of the male are transmitted 



