OBSERVED IE" HERTFORDSHIRE IE" 1883. 
193 
Frog spawn was observed at Harpenden on the 4th of Ifarch, at 
Hertford on the 6th, at Watford on the 15th, at Croxley on the 
17th, at Royston on the 21st, and at Fanhams Hall on the 7th 
of April. 
In the accompanying table, giving the dates of flowering of the 
plants in the Meteorological Society’s list,^' a column is added as 
before showing the means of the earliest dates recorded for the 
period of observation. Of the 79 species, 37 have been observed 
every year of the eight from 1876-83, 10 seven years, and 14 six 
years. There are therefore 61 species which have been observed 
at least six years. Excluding the ivy, which comes into flower too 
late to be grouped with the other species, we have 60 species which 
have been observed a sufficient number of years to be reliable tests 
of the state of vegetation in 1883 from about the end of January 
to near the end of July. Of these 60 species, 37 came into flower 
earlier than the mean of 1876-83, 20 later, and 3 on the same day 
as the mean, showing that vegetation may be considered to have 
been generally forward in 1883. The average state of forwardness 
over the mean of 1876-83 is 3 - l days. 
Half the species come into flower on the average by the middle 
of May, and, considering this period as spring, and from the middle 
of May as summer, 19 of the 30 spring flowers showed themselves 
before their mean date, and 11 after it, while 19 of the summer 
flowers showed themselves before their mean date, 8 after it, and 3 
on the same day as the mean. The average state of forwardness 
of the spring flowers was 2*8 days, and of the summer flowers 3*4 
days. 
Dividing now the period of observation into three, each division 
represented by 20 species, the average date of the first 20 species, 
from 21st Jan. to 21st April, is 6-2 days early ; of the next 20, 
from 21st April to 4th June, 2*2 days late ; and of the last 20, 
from 5th June to 24th July, 5"2 days early, showing that although 
there was a general state of forwardness, there was a decided 
retardation about the middle of the period of observation. 
The same result comes out even more clearly by dividing the 
period into six, nearly coincident with the six months from 
February to July, each period being represented by 10 species. 
The average for February is 14*4 days early, for March 2'0 late, 
for April 4-1 late, for May 0 - 4 late, for June 3"3 early, and for 
July 7*1 early. 
The retardation after the very early average for February seems 
to be due entirely to the severe frosts and continued cold of the 
month of March, the effect of which is apparent from about the 
middle of March to the middle of May. 
* In addition to the tabulated records the following observations were made in 
the neighbourhood of Watford by Dr. Brett:— 
1. Anemone nemorosa , April 10 
o. Papaver Rhceas, June 3 
12. Lychnis Flos-cuculi, ,, 3 
13. Stellaria Holostea , April 18 
14. Malva sylvestris , June 14 
30. Rosa canina , „ 4 
58. Symphytum officinale, ,, 12 
68. Primula veris , April 10 
