1920 



ENTOMOLOGICAL SOCIETY 



,4.: 



Fig. 1. Isoplianal Map oi' the United States in 1 degree isophanes and 1x5 degree 

 quadrangles to illustrate method of expressing the geographical constants of the Law. 



Fig. 2. Isophanal Map of the United States in 5 degree isophanes and 5x5 degree 

 quadrangles to illustrate method of designating phenological areas for the study of 

 influences which contribute to time, altitude or latitude departures from the geographical 

 constants. The estimated minus (earlier) and plus (later) departures in days from the 

 computed time constant for spring and autumn events, as given for each quadrangle, 

 are based on a study of more than 40,000 reports on the date wheat harvest begins and 

 on other statistics of planting and harvest dates for wheat, potatoes, etc., and represent 

 averages for the entire quadrangle. 



