February 13, 1903.] 



SCIENCE. 



243 



dieament, and immediately swam away, 

 none the worse for his terrible experience. 

 Even after this apparent evidence of re- 

 turning appetite, the hellbenders ate but 

 little of the liver that was given them. 

 Their remarkable tenacity of life is shown 

 by the fact that an individual that escaped 

 from the tank lived for three weeks with- 

 out food and water. 



Nothing was learned as to the breeding 

 habits except the fact that they will not 

 breed in captivity, unless, perhaps, they 

 are captured just before their natural 

 spawning season. 



Sense of Hearing in Fishes: G. H. Parker, 



Harvard University, Cambridge, Mass. 



To be published in Bull. U. 8. Fish 



Commission. 



The presence of an internal ear in fishes 

 led Hunter, ^Miiller, Owen and other physi- 

 ologists to ascribe hearing to these animals. 

 The fact that after the loss of the ear fishes 

 lose their equilibrium, but still respond to 

 sound waves if intense enough, led Kreidl 

 and especially Lee to conclude that the 

 internal ears of fishes were for equilibra- 

 tion and not hearing, and that sound waves 

 stimulate the skins of fishes, not their ears. 

 Fishes, therefore, feel sounds, but do not 

 hear them. Fundulus heteroclitus, after 

 having had the nerves to its integiunent 

 and to its lateral line organs cut, thus 

 rendering its skin insensitive, still responds 

 by fin movements to sound waves, but 

 ceases so to respond after the nerves to 

 the internal ears are cut. Fundulus he- 

 teroclitus, therefore, responds to sound 

 waves through the ear— that is, it hears. 



Breeding Hahits of the Yellow Catfish 



{Ameiurus nehulosus) : Hugh M. Smith. 



To be published in Bull U. S. Fish 



Commission. 



This paper is based chiefly on observa- 

 tion of a pair of fish from the Potomac 

 River in the Fish Commission aquarium 



at Washington. They made a nest on July 

 3, 1902, by removing in their mouths up- 

 wards of a gallon of gravel from one end 

 of the tank, leaving the slate bottom bare. 

 On July 5 about 2,000 eggs, in four sep- 

 arate agglutinated clusters, were deposited 

 between 10 and 11 a.m. on the scrupu- 

 lously clean bottom. Ninety-nine per 

 cent, hatched in five days in a mean water 

 temperature of 77° F. The young re- 

 mained on the bottom in dense masses 

 until six days old, when they began to 

 swim, at first rising vertically a few inches 

 and immediately falling back. By the end 

 of the seventh day they were swimming 

 actively and most of them collected in a 

 school just beneath the surface, where they 

 remained for two days, afterwards scatter- 

 ing. They first ate finely-ground liver on 

 the sixth day, and fed ravenously after 

 the eighth day. The fish were 4 mm. long 

 when hatched, and grew rapidly, some 

 being 18 mm. long on the eleventh day, 

 and at the age of two months their aver- 

 age length was 50 mm. 



Both parents were very zealous in caring 

 for the eggs, keeping them agitated con- 

 stantly by a gentle fanning motion of the 

 lower fins. The most striking act in the 

 care of the eggs was the sucking of the 

 egg-masses into the mouth and the blow- 

 ing of them out with some force. The 

 fanning and mouthing operations were 

 continued with the fry until they swam 

 freely, when the care of the young may 

 be said to have ceased. During the first 

 few days after hatching, the fry, banked 

 in the corners of the tank, were at irreg- 

 ular intervals actively stirred by the bar- 

 bels of the parents, usually the male. The 

 predaceous feeding habits of the old fish 

 gradually overcame the parental instinct; 

 the tendency to suck the fry into their 

 mouths continued and the inclination to 

 spit them out diminished, so that the num- 

 ber of young dwindled daily and the 500 



