18 AMERICAN CATFISHES. 



Regarding the breeding habits of Ameiurus nehulosus, Dean 

 (loc. cit.) says: 



In breeding habits the catfish still maintains its reputation for hardiness. It spawns 

 rapidly, even when transferred to aquaria. The eggs are one-eighth inch in diameter 

 and are adhesive, reminding one somewhat of frog spawn. The mass is deposited 

 in shallows where the bottom is sufficiently hard to support its weight. The danger 

 to the egg occasioned by stagnancy or muddiness of the water is carefully provided 

 for; the male, standing guard, forces the water slowly through them. In some of 

 the southern species, for thorough aeration, the male turns to account the operation of 

 breathing, filling the back of the mouth often so full of eggs that the whole face and 

 throat are distended. In the neighborhood of New York the spawning season is in 

 the early part of April, and appears to last about a fortnight. Toward the latter part 

 of the month the females go into deeper water. At this season (Central Park) of a 

 dozen fish caught, ten proved to be males. 



A similarity of breeding habits in Ameiurus nehulosus and Ameiurus 

 catus is shown by comparing with the preceding record of Ryder the 

 observations* presented in a paper by Dr. H. M. Smith before the 

 American Association for the Advancement of Science, and noticed^ 

 in Science (Feb. 13, 1903, p. 243). Smith observed: 



A pair of fish from the Potomac River in the Fish Commission aquarium at Wash- 

 ington made a nest on July 3,c 1902, by removing in their mouths upward 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 separate agglutinated clusters, were deposited between 10 and 11 a. m. on 

 the scrupulously clean bottom. Ninety-nine per cent hatched in five days in a mean 

 water temperature of 77° F. The young remained on the bottom in dense masses 

 until 6 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 scattering. They first ate finely ground liver 

 on the sixth, and fed ravenously after the eighth day. The fish were 4 millimeters 

 long when hatched, and grew rapidly, some being 18 millimeters long on the eleventh 

 day, and at the end of two months their average length was 50 millimeters. Both 

 parents were very zealous in caring for the eggs, keeping them agitated constantly 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 blowing 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 irregular intervals actively stirred by the barbels 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 inclina- 

 tion to spit them out diminished, so that the number of young dwindled daily, and 

 the 500 that had been left with their parents had completely disappeared in six 

 weeks, although other food was liberally supplied. 



In Sebago Lake, Maine, in a shallow, sandy pool, on July 6, the 

 writer observed one catfish {Ameiurus nehulosus), sex undeter- 



aSee also Eycleshymer, A. C, Observations on the breeding habits of Ameiurus nebulosus, American 

 Naturalist, November, 1901, p. 911. 



b For the complete account see Smith, H. M., and Harron, L. G., Breeding habits of the yellow catfish. 

 Bull. U. S. Fish Commission, vol. xxii, 1902, p. 151-154. 



c Italics by the writer to show close similarity to Ryder's observations. 



