APPENDIX. 121 



throughout the twenty-four, and this seems to be very satisfactory. 

 However, the practice of keeping the fry continually supplied with 

 food should be considered of more importance than regular feeding 

 periods. 



A mechanical feeder was used this last year which promises to be 

 very satisfactory. It consists of an ordinary flour sieve which is 

 suspended in the water and so arranged that the handle is slightly 

 turned at each revolution of the paddle. The finely ground food is 

 placed in this sieve and at each turn of the paddle a little of it is 

 scraped out into the car, where the current of water quickly spreads it. 



9. LENGTH OF TIME REQUIRED TO REACH THE FOURTH STAGE. 



The length of time required to reach the fourth stage from the 

 time of hatching varies at Wickford from 10 to 21 days. The tem- 

 perature of the water is, in a great measure, responsible for this 

 variation, but careful records kept during 1905 seem to show that, 

 while it is the most important, it is not the only factor. It will be 

 necessary to experiment further in order to fully establish the im- 

 portance of the various factors, yet it may be said that the following 

 certainly do exert considerable influence on the duration of the first 

 three stages. In the order of apparent importance they are tempera- 

 ture, food, current, density, and light. The effects of temperature, 

 food, and current have already been described. Of the influence of 

 the density of the water little is known ; after a warm rain, however, 

 molting seems to progress more rapidly. The importance of the 

 light factor is as yet undetermined. It has been the practice this 

 past year (1910) to rear the fry unscreened from the sunlight, until 

 they have reached the third stage after which they were kept screened . 

 Good results were obtained from this method. 



10. LIBERATION OF THE LOBSTERLINGS. 



The proper liberation of the young lobsters is a matter equally as 

 important as the successful rearing of them to the bottom stages and 

 great care must be taken, otherwise the results so hardily won in 



