180 PHENOLOGIICAL OBSERVATIONS 



neglecting any which give reason for doubt, when selecting 

 for summation on the form* within. Great care must also 1>3 

 exercised in copying the figures and entering them, so that no 

 slip may occur. Every entry should be checked. One slip may 

 spoil the effect of all the accurate numbers entering into the 

 summation. In like manner great care has to be taken in 

 adding and averaging the figures, and for this purpose every 

 sum should be done twice (once in reverse order), so as to 

 give absolute confidence in the accuracy of the work. 



Remarks. The compiler filling one of these blanks* should 

 keep one copy for himself while sending the other to the com- 

 piler-in-chief. 



The set of stations on the right under "when becoming com- 

 mon," must be exactly the same as on the left, under "when 

 first seen." The compiler can enter explanatory remarks in 

 the blank* below, and should sign each sheet as a guarantee of 

 its correctness. These sheets* will be bound into a volume for 

 each year." 



"These words refer to the ruled and printed blank forms into which 

 the compilers enter the averages, which are finally compiled into the 

 same blank form as exhibited in the following- table. 



Nomenclature as in GRAY'S or SPOT-TON'S MANUAL. 



