256 DESCRIPriVE KEY TO PAGES Ui TO 252 



blow air-bubbles formed of this substance, which float in a mass in 

 which the male places the eggs, immediately after fertilization, which 

 takes place in mid-water, the parent fish intertwining their bodies 

 immediately under the nest of bubbles at frequent intervals, extruding 

 a few eggs at a time. Then as the fish relax their embrace, the male 

 catches the eggs in his mouth and blows them — each one separately 

 — into the air-bubble nest. 



As soon as all the eggs have been extruded from the female and 

 fertilized in the external embrace of the parent fish, the male having 

 gathered all eggs into the floating nest, he then drives the female to 

 as distant a corner of the aquarium as possible (as he knows that 

 she will eat the eggs if she gets a chance) and for about 48 hours 

 the male fish guards the nest and eggs, re-arranges and adds more 

 bubbles where required. Towards the end of the hatching process, 

 the male spreads the nest out as much as possible, to give the hatch- 

 ing young as much air surface as he can and indeed it is difficult for 

 the newly hatched young to escape from the air-bubbles, as they are 

 held there by the attraction of cohesion. A¥ithin the next three days 

 they become independent and scatter from the nest, whereupon the 

 male fish must at once be removed. The female should be removed 

 as soon as she is observed to have finished spawning and has been 

 driven away from the nest by the male. The temperature must be 

 kept high — mid-summer temperature as in a hot-house — for at least 

 two or three months after the young hatch. The young fish being 

 microscopic must be well supplied with infusoria — the microscopic 

 dust-like form of living creatures native to most old, standing water, 

 which in turn must be cultivated. See page 51. Do not disturb the 

 young fish. They must remain in the aquarium in which they hatch 

 at all events until they are plainly recognizable as fish of their own 

 species and at least a quarter of an inch long. As soon as they seem 

 to have assumed solidity, i. e., dark, round bodies, which they should 

 have at j/j-inch long — they should be fed with finely-strained young 

 daphnia and from that time on the growth is rapid. All young fish — 

 of whatever kind — which outgrow their fellows, must be separated into 

 other aquaria or compartments, as otherwise they starve or eat the 

 smaller ones. 



B7a GROUP 



LABYRINTH FISH WHICH BUILD NO NESTS but deposit 

 their spawn loose and floating in or on the water. This class includes 

 the Snake-heads (Ophiocephalidse) and the Climbing Perch (Ana- 

 bantid^e). Hardy fish, generally accustomed to living in cooler water 



