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ANNALS NEW YORK ACADEMY OF SCIENCES 



On the consecutive map of 11)02, the western antipleion is very much 

 less developed than on tfie (le{)artiire map of 1902 (Fig. 24)- This is 

 evidently due to the fact that the normals adopted in the ''Montlily 

 AVeather Ecview" are very diil'erent from the means of 1900-1909. 



The following diagram (Fig. .34) gives the successive positions oi the 

 quasinonnal line on the maps ending with October, 1902, December, 1902, 

 February, 1903, May, 1903, and August, 1903. Figures 35-37 are the 

 consecutive maps for the years ending with September, October and Xo- 



PiG. 34. — Displacements of the quasi- Fig. ZQ. — Deimriurcs of teiniierature 

 normal line averages for Moremher, l<!02,-()ctoher, 



um 





Fig. 35.- — Departures of temperature 

 averages fur October, I902,-8eptember, 

 1903 



Fig. 37. — Departures of temperature 

 averages for December, 1902,— Novem- 

 ber, 100$ 



vember, 1903. These diagrams show ])lainly tliat we do not have to 

 deal with a simple displacement from west to cast or southwest to north- 

 east. 



We see that the pleion and antipleion are not only dependent upon 

 each other for their displacements but also have a tendency to remain on 

 the continent. The antipleion moving eastward displaces the pleion, 

 first northward then northwesiward and finally westward. The pleion 

 and antipleion move en hloc conira-elockwise. 



