PHILOSOPHICAL SOCIETY OF WASHINGTON. 81 



tidus, Chrysosplenium Americanum, and often Anemone hepatica. 

 The number regularly found in flower in March is quite large and 

 in special years very large. It was of course impossible to make 

 observations every day of any year, but taking a number of years 

 my observations cover nearly every day of the spring season. As 

 showing the number of these early vernal species and also how 

 widely the seasons may differ, the following facts are presented : 



In the year 1878 seventeen species had actually been seen in 

 flower and noted up to March 24th. I did not go out again that 

 year until April 7, when I enumerated forty-six additional species, 

 making sixty-three in all up to that date. This was an exception- 

 ally early season. The next spring, that of 1879, was a backward 

 one, as is shown by the fact that while I had visited the same 

 localities, and taken notes with equal care only thirty-three species 

 had been seen in flower up to April 13th : twenty -nine species which 

 had been seen in flower on April 7th, 1878, were not yet in flower in 

 the same localities on April 13th, 1879. There appeared to be about 

 three week's difference in these two seasons. The last season, 1880, 

 was again an early one, though less so than 1878. It was, however, 

 near enough to the average to render the facts observed of great value. 

 The follo'wing are a few of them : On February 29th, seven species 

 were seen in flower in the Rock Creek region. On April 4th, thirty 

 were enumerated on the Virginia side of the Potomac, above the 

 Aqueduct Bridge. On April 11th, eleven were seen in addition to 

 those previously enumerated in the Eastern Branch region : and on 

 the 18th of April, High Island was visited, and twenty-nine added 

 to all previously recorded, three of which were then in fruit. The 

 total to this date was therefore seventy cpecies. This season I con- 

 cluded was a week or ten days later than that of 1878, and as much 

 earlier than that of 1879.* 



* Since the above was written the present season (18S1) has passed its vernal 

 period. It has proved still more backward than 1879 anc ^ tne latest spring thus 

 far observed. On April 3d, I made my first excursion and visited the Virginia 

 side of the Potomac above Rosslyn. Only 7 species were seen in flower including 

 Alnus serridata which doubtless can be obtained much earlier in ordinary years, 

 but has been oveilooked. Besides Draba verna, a January species, and Anemone 

 hepatica, a February one, the only herbaceous flower found was Sanguinaria 

 Canadensis. On April 10th, High Island was visited, but only 8 species could be 

 added to the above 7, and several of these, as Jeffersonia diphylla, Dicentra cn- 

 cullaria, Saxifraga Virginiensis, Erythronium Americanuvi, and Stellaria pu- 



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