72 NATURAL HISTORY OF AMIA CALVA LINNAEUS. 



seven times — six times at night and once by day. That in these cases roiling of the 

 water is not due to the movement of the fish in leaving the nest is shown by the fact 

 that it occurs only on the nest and not outside it (i.e., the fish leaves no trail of roily 

 water), and by the further fact that roiled nests have been seen six times at night and 

 only once by day. Two of these nests were visited at 9 p.m., found to be roiled, and 

 the amount of work done on them noted. They were visited again at 4.30 a.m., and 

 it was found that in the interval the work had been carried much farther. All this 

 shows that the fish works chiefly by night, not by day. On one occasion a male 

 Amia was found lying by day on a half -completed nest, and thinking to see how he 

 worked at the nest, "I watched him continuously for two hours. For one and one- 

 half hours he remained absolutely quiet, not moving even the fins. During the 

 next half -hour he moved once about six inches and at another time turned around. " 

 Since that time males have been reported to me as having been seen assiduously 

 circling on the nests by day, but I have never seen this myself. Only twice have 

 I had evidence of an Amia working at the nests by day. In the first case, "as 

 I came near the nest the tail of the fish could be seen above the water plants, as 

 though he were working head down. Upon approaching, a male was seen lying on 

 a nearly completed nest." In the second case a half -completed nest found at 

 9 a.m. on April 23 was found completed in the afternoon of the same day. Since 

 the work is done chiefly at night, it is not likely that the method of work will ever 

 be accurately observed. 



Over nests that are in process of making or recently finished one often finds 

 floating the young shoots of water plants. These have the appearance of having 

 been sharply cut off and are as a matter of fact probably broken off by rubbing 

 or bitten off by the male fish. Some of these measured 7 to 16 centimetres long 

 and 2 to 5 millimetres in diameter at the base and appeared to be the young 

 shoots of cattail. Another was a cutting of Potamogeton 8 centimetres long. 

 Such cuttings are especially apt to be noted over empty nests visited early in the 

 morning and afford a further indication that the work is done chiefly at night. 

 Often by means of these cuttings I have discovered nests that were so hidden by 

 the floating leaves of the last year's cattails as to have remained otherwise quite 

 undetected. 



That the male uses the snout in making the nests is indicated by the fact that in 

 the nesting season the snout of the male is frequently covered with scratches where 

 the epidermis has been removed and the underlying connective tissue shows white 

 beneath it. Probably the male in building the nest breaks off the young shoots with 

 the snout or by the movements of the body or by biting (see also Dean, '98). Prob- 



