How to obtain it. 161 



natural habitats, and should it make its appearance, depend upon 

 it something is wrong somewhere. Three conditions are necessary 

 for the avoidance of Saprolegnia (i) Darkness; (2) thorough 

 cleanliness throughout ; (3) and all wood to be carbonized. 



Light is highly favourable to its growth, and darkness is 

 unfavourable. Darkness is also good for the eggs, and light is 

 the reverse; indeed, too much light is calculated to injure the 

 embryos. Therefore, keep the boxes always covered. As regards 

 cleanliness, it should not be necessary to say much, and yet I 

 know it is sadly too often the case that for want of it the eggs 

 suffer. The filters should be thoroughly effective, and every 

 precaution taken to keep the hatching boxes perfectly clean during 

 the period of incubation. Every scrap of woodwork below water- 

 line should be charred, and all the joints. and knots or any other 

 places that look at all suspicious should be varnished also the first 

 season. For the second season at least two coats should be 

 applied, and each succeeding season afterwards one or two coats, 

 as may be deemed desirable. Especially about any nail heads, 

 and the corners and crevices of the grilles should the varnish be 

 applied. 



The inside of the boxes should never be too roughly scoured 

 out after they have been varnished for the season. It must be 

 remembered that every scratch or puncture which lays bare the 

 wood, creates a suitable nidus for the germs of the fungus. I 

 have seen cases in which such little regard has been paid to this 

 that there has been little cause for wonder at an outbreak of the 

 deadly pest. Should anything go wrong with the filters and the 

 eggs get covered with sediment, there is at once a danger of 

 fungus making its appearance. The two things often go together. 



The eminent American fish culturist, Livingstone Stone, 

 says : " There is no word in the fish breeders' vocabulary that is 

 so associated with loss and devastation as the word 'fungus.' 

 There is nothing with which he has to deal that is so insidious 

 and deadly. This silent invisible foe is sure to come if any door 

 is left open for its entrance. It often fastens its irrevocable grasp 

 on the eggs, without giving any sign of its approach. Once 

 present in the water it spreads over everything. It cannot be 

 removed. It never lets go its hold. It is fatal in its effects." 

 M 



