FLORA OF WASHINGTON AND VICINITY, 27 



spring. There are a few plants which may sometimes be found in flower 

 here in January, such as Siellaria media, Taraxaciim Dens-leonis, or Acer 

 dasycarpum (collected January 17, 1876, in the city), in favored places; 

 but these will bloom at any time when a few days of mild weather with 

 sunshine can come to revive them. There are, however, several strictly 

 vernal species, which bloom quite regularly in the latter part of Feb- 

 ruary, such as Symplocarpus fcetidus, Chrysosplenium Americanum, and 

 often Anemojie Hepatica. The number regularly found in flower in March 

 is quite large, and in special years very large. It was, of course, im- 

 possible to make observations every day of any year, but taking a num- 

 ber 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, 17 species had actually been seen in flower and noted 

 up to March 24. I did not go out again that year until April 7, when I 

 enumerated 46 additional species, making 63 in all up to that date. This 

 was an exceptionally 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 33 species had 

 been seen in flower up to Ai)ril 13. Twenty-nine species which had been 

 seen in flower on April 7, 1878, were not yet in flower in the same locali- 

 ties on April 13, 1879. There appeared to be about three weeks' differ- 

 ence 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 following are 

 a few of them : 



On February 29, seven species were seen in flower in the Eock Creek 

 Region. On Aj^ril 4, thirty were enumerated on the Virginia side of the 

 Potomac, above the Aqueduct Bridge. On April 11, 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 species. This season I concluded was 

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

 that of 1879.* 



We may now inquire what some of these early plants are. 



* Since the above was written, the present season (1881) has passed its vernal period. 

 It has proved still more backward than 1879 and the latest spring thus far observed. 

 On April 3 I made my first excursion and visited the Virginia side of the Potomac 

 above Rosslyn. Only 7 species were seen in flower, including Alnus serrulata, which 

 doubtless can be obtained much earlier in ordinary years, but has been overlooked. 



