THE AQUARIUM, JANUARY, 1894. 



83 



spawn, though a large fish will deposit 

 more eggs than a small one. As an in- 

 stance, goldfish, one inch in length, 

 nine months old, sjiawned in an aqua- 

 rium kept in a parlor ; all the eggs 

 hatched and the young grew up. Gold- 

 fish can be made to spawn from March 

 till October. 



The young are hatched out in from 

 two to six days, the period of incubation 

 being determined by the temperature 

 ■of the water and the condition of the 

 Aveather. Direct sunlight has the effect 

 of hastening the process. The fish 

 arrive at maturity the season after 

 hatching, and are then ready to repro- 

 duce in their turn. During the first 

 few weeks the young fish are devoid of 

 coloring, being of a silvery gray. At^ 

 six weeks old this color begins to change, 

 the fish gradually turning darker and 

 then assuming the rich yellow, the back 

 and fins sometimes becoming black. 



The perfection and rapidity of the 

 coloring process depend upon several 

 causes, foremost among which is the 

 proper selection of specimens from 

 which to breed. This is an important, 

 in fact the prime factor, upon which 

 hinges the character of the result. The 

 parent fish should be those selected 

 from among the very best, and also 

 having obtained their coloring during 

 the same season that they were hatched. 

 And now comes an essential point, the 

 determination of which has hitherto 

 been impossible, and that is the certain 

 distinction of the sexes. This indeed is 

 a, difficult matter, and can only be re- 

 vealed to the practiced eye of the pisci- 

 culturist. 



It was formerly supposed, and is yet, 

 that the male was always that one hav- 

 ing a short dorsal fin. As previously 

 stated, such a specimen is a deformity. 

 It is true, however, that about three 



out of five of th'ese short dorsal fin fish 

 are males, but the existence of an ex- 

 ception to the extent of forty per centum 

 is quite sufficient to impugn the validity 

 of the rule. 



For some years past the author has 

 experimented upon and investigated the 

 subject, with the avowed determination 

 of forever putting at rest all contro- 

 versy upon the question. During the 

 breeding season, as that is the only 

 period when any difference is observ- 

 able, the male can invariably be distin- 

 guished by the presence of small white 

 tubercles on the gill covers and the first 

 ray of the pectoral fins. 



The author is substantiated in this 

 statement, fo]' it will be remembered in 

 the description of the Carp, that that 

 fish during the breeding season presents 

 tubercles on the head. The goldfish 

 being a species of the Carp family, it is 

 not unnatural that a trait or peculiarity 

 of one species should reappear in 

 another. 



The selection of the male having now 

 been made, the next step is to procure 

 the best female. It is an old rule with 

 breeders " never to use stock you don't 

 know, to breed from,'' and is a law to 

 be respected in raising ornamental fish, 

 applying especially to the fancy varie- 

 ties of goldfish, hereafter to be de- 

 scribed. 



When hatched, the young fish are 

 further subjected to modification by 

 their surroundings ; the temperature of 

 the water, its depth, quality, etc., all 

 I exercising more or less infiuence. The 

 complete result of the breeding, so far 

 as the coloring is concerned, cannot be 

 seen until the change has taken place, 

 and then any errors that have been 

 made are at once apparent. 



Those fish that have failed to receive 

 any coloring are then called silver-fish ; 



