l88 MAINE AGRICULTURAL EXPERIMENT STATION. IQII. 



nests in use on the Station plant. The figures given inchide all 

 eggs laid on the plant regardless of what experiments the birds 

 were in. The number of birds on the plant varied from time 

 to time, so that the totals in this table are not to be used as an 

 index of the laying of the stock. For example it will be noted 

 that whereas in July, 1909, 6106 eggs were obtained, in the 

 following month there were only 504. This might be taken 

 to indicate a tremendous drop in the rate of fecundity of the 

 birds, but actually it merely means that on August i, 1909, the 

 houses were cleaned out and all the laying birds were sold 

 except a small number kept over for breeding purposes. In 

 this table the column headed "Nest Eggs" gives the number 

 of eggs laid in the trap nests in such way that the bird which 

 laid each of these eggs was known. The column headed "Un- 

 recorded Eggs" gives the number of eggs laid on the floor of 

 the pen or in some other situation such that it was not possible 

 to know the individual hen which laid each egg. 



In order that the data set forth in this table may be more 

 readily comprehended fig. 90 has been prepared. In this dia- 

 gram the trend of the percentage figures during the last three 

 years is shown. The zigzag line in each case represents the 

 observations. The straight lines are fitted to these observation 

 lines by the method of least squares. The equations to' these 

 lines are as follows, 3,' denoting "percentage of unrecorded eggs 

 the nest eggs," and x denoting months, the origin of x being 

 taken as one month before the first observation of the laying 

 year, viz. that for September : 



1908-09 y=:2.44 — .14 X 



1909-10 3/^1.93 — .094.1- 



1910-1 1 3/=o.92-|-.029.i- 



This table and the diagrams show that : 



( I ) ■ The residual error was more than three times as great 

 with the old type of trap nest as it is with the new. Taking 

 the three laying years, 1908-09, 1909-10, and 1910-11, together 

 the grand totals are: 151,355 nest eggs and 1881 unrecorded 



