194 



NATURE-STUDY REVIEW 



[11:4— Apr., 1915 



be carried in one's pocket bound between board covers. By 

 means of these cards, as examination will show, a record may by 

 kept of the daily observations, together with weather conditions, 

 time of day, date, etc. The left hand column may be used en- 

 tirely for the recording of the species, names, and the right hand 

 column for remarks concerning abundance, place of observation, 

 etc. ; if mere identification be desired, both columns may be used 

 for species names. The reverse side of the card is ruled also and 

 may receive records in the same way. These field records may 

 then be filed as made. 



No. i 



Observer. 



The migration record is made on another card (No. 2), which 

 provides for both spring and fall appearance. It is commonly 

 customary to record the first appearance of any member of a 

 species as being typical of its kind. This is seldom true, since 

 stragglers frequently wander well ahead of the main body, and 

 their appearance does not, therefore, mark the main advance. 

 Herein lies the advantage of the Field Records on which one may 

 find, if they be well made, not only the date of first appearance, 

 but also that of maximum abundance. To make this distinc- 

 tion in the record clear, two dates may be used on the Migration 

 Card, the first date for the first appearance, and the second to 

 mark the crest of the wave. 



