NATURAL HISTORY OF AMIA CALVA LINNAEUS. 81 



at 3 P.M. and again in the nest at 4 P.M. On the afternoon of April 29 a male was 

 again in the nest for several hours. On April 30 at 3.30 P.M. two males were seen 

 lying on opposite sides of the nest. At 3.50 P.M. a male and a female were in the 

 nest and the spawning was seen to take place. On the next morning the nest was 

 found to be well filled with eggs. 



Nest 41, found on April 25 at 4 P.M., contained then about twenty eggs in a 

 late pre-embryonic stage. On April 26 at 2 P.M. the nest was empty and the male 

 absent. On April 29 at noon the nest was full of eggs in an early pre-embryonic 

 stage. At this time I had not learned to identify individual fish, and since then I 

 have had no opportunity to repeat the observations. In another paper I shall 

 describe a case in which an individual male of Eupomotis gibbosus reared in one 

 nest two broods from eggs laid at quite different tunes by two females, and I have 

 no doubt that, as indicated by the observations given above, this happens also 

 with Amia (see Whitman and Eycleshymer, '97). 



That an individual female may spawn in more than one nest is also highly 

 probable. This, I take it, is what happened in the case of the five nests referred 

 to above, in which eggs were laid in the enclosure supposed to contain only males. 

 These nests were in two groups, one consisting of nests 71 and 73, near one another, 

 and the other of nests 79, 80, and 81, about five metres apart. All five nests contained 

 eggs in nearly the same stage (within two to four hours), and the total number of 

 eggs in the five nests was not more than is often found in a single nest. This indi- 

 cates that they were laid by one or two females. In this case an individual female 

 upon leaving one nest in an interval of spawning probably found herself near a 

 neighboring nest and was brought into this second nest by its occupant and there 

 spawned. This view is the more probable since this is again precisely what happens 

 in the case of Eupomotis gibbosus, and since in two of the four cases in which the 

 spawning of Amia has been actually observed other males than the owners of the 

 nest have been seen in the neighborhood. If the nests of any season were carefully 

 platted on a map and the stage of development of the eggs carefully noted, I should 

 expect to find frequently that adjacent nests have eggs in nearly the same stage 

 of development, but unfortunately I have not located on my sketch-maps a suffi- 

 cient number of nests to throw further light on this point. 



I have made numerous attempts at artificial fertilization, but I have never found 

 it possible to strip the female fish. Twenty-one females were taken in a fyke net 

 during the spawning season as they were going to the spawning ground. These 

 were confined in a crate, as already described. The fish were removed daily for 

 eight days and examined by an experienced spawn-taker, to see whether they were 



