532 ANNALS NEW YORK ACADEMY OF SCIENCES 



sluggish in movement and are provided with a swimming apparatus 

 altogether too inefficient to enable them to dash up the high and frothy 

 falls. 



At one time, the writer had occasion to divert the water of a small 

 mountain stream so that access could be gained to a deep pot-hole from 

 which the water, rock and gravel were subsequently removed. This pot- 

 hole was twenty-two feet deep, nearly circular in horizontal cross-section 

 and it varied in diameter from six to ten feet. Generally, the sides ap- 

 proached the vertical and in some parts inclined inwards. When the 

 water had been lowered to within four feet of the bottom, the remaining 

 water was seen to contain a large number of "capitanes." They were 

 greatly excited and distressed and were swimming and creeping about 

 in all directions. A small stream of water in a thin film ran down one 

 side of the pot-hole from a leak in the dam above. Several fish, after 

 nosing around the edge of the water, discovered this small inflowing 

 stream and started to creep up in it, but becoming frightened by the 

 movements of the working men near, dropped back. When work was 

 stopped for the noon hour, four of the smaller fish started up, following 

 the thin stream of water. The water ran over their noses, down their 

 backs and trickled off their tails in small streams. They would hitch 

 themselves up rapidly for the distance of a foot or so and remain quiet 

 for a minute or two ; then another foot and another rest. In half an 

 hour, the four had reached the water in the pool at the foot of the dam 

 above. In making the ascent, they were obliged to pass a part of the 

 wall, about two feet in length, that inclined inward at an angle of about 

 30° from the vertical. When they reached this overhanging part, in no 

 observable manner did they change their tactics, but they ascended it as 

 rapidly and safely, and apparently with no more effort than the other 

 portion of the wall. During the afternoon, several more of the fish 

 climbed out. A large number were in the water at the bottom of the 

 hole when work was suspended for the evening. In the morning not a 

 fish remained. 



For the greater part, the path followed by the fish in making their 

 ascent lay over smooth, water-worn surfaces free from any coating of 

 vegetable matter. The upper part, however, was covered by a thin film 

 of an alga-like growth that may have served for the engagement of the 

 sharp-pointed teeth on the movable ventral fins. The total vertical dis- 

 tance through which the fish climbed measured eighteen feet. When 

 undisturbed, they covered the distance without a slip or fall. The water, 

 diverted around this pot-hole, flowed through a large pipe and fell from 

 the end upon the steeply inclined water-worn rock at the side of the 



