Thomson. — Protection of the Undersized Fish 173 



ients may lose their cards they will never forget the in- 

 structions on protection given at the hatchery. 



When we take into consideration the time and care 

 that it takes through artificial propagation to bring one 

 of our trout to the fishing limit of seven inches, and that 

 one grasp of the dry hand, in taking an undersized fish 

 from the hook for returning it to the water, removing 

 nature's protection so that the fish will die after being 

 returned, it seems to me that the American Fisheries 

 Society should push the matter of education for the pro- 

 tection of the undersized fish as far as possible. 



DISCUSSION 



1 would like to take a few moments' time in demonstration. 



( Mr. Thomson here produced from a wooden box a sealed tube of 

 glass about one-half inch in diameter and about four feet in length, 

 containing specimens showing the various stages of growth of the fish.) 



I can give you an exhibit here in this tube, of the stages from the 

 time the eggs are taken from the fish until the fish are ready for the 

 stream. 



In our hatchery in Estes Park, the water stands at 46° ; and it 

 changed but two degrees last winter. 



We take the eggs after they are fertilized and place them on the 

 hatching trays, and they will require 40 days to reach the stage shown 

 in this glass tube, when they are hatched out. 



From the time the eggs are placed on the trays to the eyed stage. 

 which is the stage when the Government do their shipping, it will take 

 25 days in a temperature of water standing at 46°. At this stage they 

 can be packed in moss and kept at a temperature not colder than 38°. 

 When the Government ships eggs to Japan and Australia, they ship 

 them in the eyed stage. 



You will see from the tube that after 35 days much greater prog- 

 ress is shown, and you can see the fish curled up. 



In 40 days you will see the fish as they have passed from the egg 

 state to the absorption state. There is a spot on the shell of the egg 

 where each fish has passed through, as you will see in the tube. 



Ten days after the hatching out you will see them at this stage. 

 Then in 20 and 30 days they rise to hunt food. You will notice the 

 development in 20 days and the further development at 30 days. 



You will see here then the whole process of development, from 

 the time the eggs are placed on the tray, until they rise to hunt for 

 food, when we begin feeding them. 



