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TEE AMERICAN NATURALIST [Vol. XLI 



three specimens were found which had, through some mishap, been 

 left with only stumps of their snouts. Fig. 2 shows a photograph 

 of such a fish. In each case the fish was large, two being nearly 

 four feet in length and the other measuring four feet and seven 

 inches. In each the injured part of the snout was well healed, 

 but no indication of regeneration of the organ was shown. It is 

 evident from these individuals that this fish without the aid of 

 its snout is capable of procuring food eiiough to maintain a large 

 body. Moreover if the appendage was lost while they were yet 

 small, they had succeeded in increasing in size without their 

 "spatula with which to agitate the mud." 



Fishermen state that large holes are often rooted out in the lake 

 bottoms by the digging of Polyodon with its "paddle." In the 

 bottoms of drained lakes, places resembling " hog- wallows " are 

 found, which Polyodon is thought to have dug while feeding. 

 Such statements are difficult to substantiate and yet there is prob- 

 ability that they are true, for there are immense numbers of 

 Polyodon herded in one of these almost land-locked lakes, and 

 they feed over the muddy bottoms. 



Observations on the general behavior of this fish lead me to a 

 rather skeptical position regarding the foraging value of the ros- 

 trum. I am inclined to regard it more as a tactile organ since 

 the sense of sight is of so little use to the fish while swimming 

 forward. Again its use for digging seems to be restricted as in- 

 dicated by the actions of this fish when its rostrum strikes against 

 any foreign object. When, for example, Polyodon is surrounded 

 by a seine and happens to swim against the net at any place, it 

 very often stops when its rostrum strikes the net; sometimes it 

 continues to push forward by one or two indifferent efforts, and 

 then gives up entirely, turning over on its back and floating along 

 the cork-line of the seine. In a large liaul fifteen or twenty fishes 

 may be counted floating along the cork-line with their white ventral 

 surfaces turned upward. Sometimes tliey may Hoat thns on the 



by the fisherman who guards the line in a row-boat, in order to 

 catch the fish that float over while the seine is being hanled in. 

 The larger and more active fishes often strike the seine several 

 times before surrendering, but even they show but little ability 



