446 PARENTAL CARE AMONG FRESH-WATER FISHES. 



In two nests wliieli were found beneath logs on Juno 11, the parent fishes were 

 naoving about in the small sheltered excavation. The eggs were removed in 

 each case ; those of one lot were in early cleavage, while those in the other were 

 in late gastrula. Both nests were visited on the following day, but the fishes 

 were no longer present. Another nest, in which the eggs were in late gastrula- 

 tion stages, was uncovered and left exposed. When visited on the next morning 

 neither fish nor eggs were found. 



While the nest is thus bravely guarded in many if not most cases, 

 it is not in all. In fact much individuality appears manifest in the 

 behavior of the fish toward the i)recious deposit wdiose care it assumes. 

 Professor Birge had the ojiportunity to see many individuals and has 

 given his impressions in excellent form : 



There was a surprising difference in the disposition of the fishes on various 

 nests. One of them was extremely tame. If approached cautiously, he would 

 not swim off, and it was quite easy for me to put my hand under him and lift 

 him off the uest. He seemed to enjoy being scratched gently, and when lifted 

 oft' the eggs would remain where placed or would swim oft" a short distance, 

 and, in general, was very little disturbed by handling. Others were exceediugly 

 shy, so that as soou as one had approached within a few yards of them they would 

 dart off, throwing the eggs out of the nest as they went, with a jerk of the tail. 

 Of course they always came back and brought the eggs together again. But 

 this violent treatment of the bunch of eggs was apt to break it up, and I 

 observed that a considerable portion of the eggs was lost in such cases. One of 

 the catfish whose eggs were in a stump was particularly ferocious, and this 

 was the only one which I found that had a violent disposition. I found the 

 nest and put my hand down into the stump to take some of the eggs, when the 

 fish seized it and worried it with all his force. After that I found it necessary 

 to remove the eggs from this nest with a pair of long forceps, which the fish 

 would bite in spite of being rapped on the nose with them rather vigorously. 

 It was this difference in disposition that especially attracted my attention in 

 studying the catfish. 



If disturbed on the nest, the actions of the i:)arents are characteris- 

 tic. Eyclesheimer has recorded experiments on a pair : 



It was interesting to watch the actions of the fish when the sheltering object 

 was removed. A fence rail covering a nesting pair was carefully turned, when 

 the fishes immediately sought its shelter. As it was turned farther and farther 

 from the nest they followed, keeping as well secluded as possible, the while 

 moving restlessly about in search of the nest. When the rail was finally lifted 

 from the water the male lingered for a few moments, then darted for deeper 

 water. The female approached the shore and began searching here and there 

 for her lost nest. This she passed several times without I'ecognition, although 

 she seemed to know the surrounding landmarks, since she would go but a short 

 distance in either direction, then turning, would pass back to the locality of 

 the nest, which she found in a short time, and despite the fact that it was 

 unsheltered, she remained. On the following morning the nest was visited, but 

 again neither fish nor eggs were to be foimd. 



It is not difficult to allure the fish to an improvised shelter. A number of 

 boards were placed on the shore with one end projecting into the shallow water. 

 The fishes sought these places and made their nests beneath the boards. It is 

 worthy of note that in no case did I observe more than a single nest beneath the 

 same cover, and this quite agrees with the pugnacious character of the fish. 



