209 



ECOLOGICAL CROSS SECTION OF THE MISSISSIPPI. 



4 



as shown by the perennial nature of the tomato and the 

 lium and Lantana Camara in California as contrasted 

 conditions prevailing at St. Louis, 

 comparison of various phenological data leads to the 



. rule 



of the country 



which are summer 



ing 



greatest 



be 



of Treleasei''^ 



"In a country covering nearly twenty-five degrees of 



latitude and fifty-five of longitude, with lofty mountains 

 and tablelands and low valleys, diversified by great lakes 

 and rivers, and embracing every variety of chmate from the 

 subtropical to the subarctic, with excesses of humidity m 

 one redon and of drought in another, it is impossible to ar- 



phenomena 



data obtainable, however 



eral features are found common to a great part of the country. 

 Whatever their exact date of leafing or flowering may be, 

 there are certain genera— like the maples, poplars and elms 

 among trees, and the violets and wake robins among herbs— 

 that precede most of their fellows; and, except in very 

 anomalous seasons, their species succeed each other with the 

 same regularity. \Vhere the same plant extends from the 

 Gulf to New England, it naturally blooms earlier in the warmer 

 rpmnn- hut it is noticcable that the difference, greatest in 



/ 



becomes less marked 



northern 



summer 



summer and autumnal 



same 



rule 



e, and is now an 

 wide distribution 



From the above will be gathered the aesiraDinxy oi 

 nVincT nf a larffc number of accurate observations such 



W. Blooming Times for Flowers. Science Almanac. 6. 



1885. 



14 



