FISH HATCHING ON A MODEST SCALE 429 



flowing and to maintain a careful watch upon the ova, 

 for which purpose the hatchery will be visited daily. 

 A few matters of some practical importance may be 

 referred to as applicable to the present stage. 



Stress has been laid upon the advisability of keep- 

 ing the eggs in exact uniformity on the glass grilles. 

 The reason is that, so arranged, any speck of foreign 

 matter, and any dead or barren or diseased egg, will 

 be detected at a glance, just as a defect of uniform in a 

 soldier will be detected in a regiment drawn up in line. 

 The eggs themselves should never be handled, but 

 arranged and rearranged on their racks with a stiff 

 feather. A small glass syphon tube, one end closed 

 with indiarubber, will suck up, after a pressure of the 

 thumb, any egg for closer examination. I f the slightest 

 trace of white fungus is observed upon it, the egg should 

 be at once destroyed, for the fungus growth develops 

 very rapidly if not checked. Careful charring of all 

 wood used in the construction of the boxes, cleanliness 

 of all utensils, and careful examination of the eggs, are 

 the best preventatives. 



A thermometer, several syphon tubes, two or three 

 clear glass wineglasses, a tiny gauze landing-net, and a 

 bunch of seagull wing feathers should be always at hand. 



The eggs are almost as easily examined in the 

 baskets as on the grilles. All one has to do is to take 

 each basket in turn, raise it an inch or so in the water, 

 and press it down again firmly. The water, rushing 

 in through the perforations, will cause the eggs to boil 



