202 On the advance of Spring, 



enl observation and experience. But where the same plants 

 are observed in successive years in the same situation at their 

 earliest flowering, there is scarcely room for any thing indefi- 

 nite or uncertain. T may mention in this place, that the exact 

 time of earliest flowering is when the pollen or dust of the 

 anthers begins to be shed. 



The most favorable situations for early flowering are steep 

 rocky cliffs facing the south. Ordinary favorable situations 

 are declivities and banks of rather light and not too moist soil, 

 facing the south and south-east, and especially the latter, as 

 they are thus sheltered from the cold north-west winds. In 

 wet clay soil, vegetation is always backward, especially for 

 plants which flower near the surface; and I have observed that 

 in the cold clay soil of Argilla district, in Ipswich, even the 

 common cu-ltivated willow flowers three or four days later than 

 in the light soils of the centre of the town. 



The observations upon which the following tables and state- 

 ments are founded, were made in Ipswich, Wass., which is 

 about twenty-five miles north-east from Boston, in lat.42° 41', 

 and in Ion. 70° 50' west from London. The places of ob- 

 servation are near the centre of the town, in rather light soil, 

 and from ten to forty feet above the level of the sea, from 

 which they are distant about three miles. Though there are 

 no high rocky cliffs facing the south, yet many of them are 

 warm, sheltered, and decidedly favorable. According to my 

 observations at several times, the season at Ipswich is two or 

 three days later than in the towns of warm soil adjoining Bos- 

 ton on the south and south-west, and scarcely later at all than 

 in the towns of clay soil on the east of Boston. In Salem, 

 Mass., ten miles south-west of Ipswich, vegetation is proba- 

 bly about a day earlier than in Ipswich. About the city of 

 New York the spring is generally several days, and sometimes 

 even a week earlier than about Boston. At Springfield, 

 Mass., it is nearly the same as at Boston, but this season it is 

 much earlier, as the newspapers mention that the cherry trees 

 began to flower there as early as May 12th. 



When cold easterly winds prevail greatly on the sea-coast, 

 but are not sufiiciently violent to extend into the country, the 

 season is sometimes more advanced there at the last of May 

 than in Boston, and that even in places situated sixty or seven- 

 ty miles to the north-west of that city. 



It is a somewhat curious fact, that while the flowers of 



