44 CORA D. REEVES. 



are held nearly at right angles to his body often with their lower 

 margins on the gravel. His anal fin is extended on one side of 

 the female close against her body while his caudal fin is applied 

 to her tail on the side opposite his anal. The position of the 

 male is largely maintained by the firm hold given by pressing 

 his ventral fins against the rough ctenoid scales of the female, 

 while the backwardly directed spinules on his scales hinder his 

 slipping backward and the spinules on her scales keep him from 

 slipping forward. The crossing of the tail of the female by that 

 of the male is frequently not maintained during spawning but 

 seems to be the means by which the motion of the two fish is 

 started in unison. 



3. The Spazvning Act. 



When thus placed (Fig. 3) the male vibrates the head in the 

 agitated trembling manner already described. This seems to be 

 a stimulus for the spawning for usually the two fish begin at once 

 a movement of the posterior portion of their bodies from side to 

 side in unison. The motion is a very rapid vibration through 

 only a short distance and lasts for several seconds. During this 

 time the sand and gravel are stirred up and make a cloud which 

 partially obscures the fish. At the same time the caudal fin of 

 the male slips over that of the female so that it is on the same 

 side of her body as his anal. That the eggs and milt are ex- 

 truded at this time was proved by picking up the fertilized eggs 

 immediately after the spawning had taken place. The eggs are 

 adhesive and remain sticking to the gravel which forms the bot- 

 tom of the depression in which they are deposited. Here they 

 were found a number of times with the help of a reading glass, 

 and were scooped up with the gravel in a bacteria dish and were 

 found to be identical with those obtained by stripping the female. 

 They are spherical, and measure about 1 . 5 mm. in diameter. 

 They are pale yellow in color and contain a large oil drop. Only 

 from one to six eggs were obtained at one time by stripping the 

 females, but large individuals deposit probably twice or three times 

 that number. Although the milt is of a milky color it is not shed 

 in sufficient quantity to be seen in the cloud of sand stirred up 

 by the rapidly moving fish. 



