326 REPORT-——1845. Uf 
behind those which come up in the spring. We admit of no exceptions 
except as to the autumnal cerealia, such as rye, wheat, or winter barley, 
which are always sown about the same time, and the phenomena of the ve- 
getation and flowering of which form the most important point in annual 
observations, from their relating to plants so extensively cultivated. The 
period of their being sown and that of the appearance of the ear should be 
noted. 
From what we have said it is evident that the plants to be examined should 
be perennials or woody. The latter are especially important, because they 
are more subjected to the double combination of atmospheric and terrestrial 
modifications ; and again, because they are better adapted than perennials for 
observations on the foliation. 
It is of importance that the plants destined for daily observation should 
have been planted at least a year; for it is well known that vegetables trans- 
planted in the spring present too much uncertainty in the periods of their 
foliation and flowering, these periods being then subordinate to the formation 
of the roots. 
In the choice of plants for observation we must avoid those which, flow- 
ering through all the year, have formed their buds before winter, such as the 
dandelion, chickweed and common groundsel, because these plants have no 
determinate period, and the time of their flowering in early spring is irregular. 
All those cultivated plants which yield varieties by culture must be equally 
avoided, as Tulipa Gesneriana, the rose-tree, the pear-tree, the cherry-tree, 
the large-leaved lime-tree; experience shows, that amongst varieties produced 
in this manner from seed-beds, some flower frequently fifteen days before the 
others. To be satisfied of the comparative value of the flowering of these 
plants, it would be’ necessary to observe everywhere the same variety, which 
is often impossible. 
Such plants as are too nearly allied in respect of species, and difficult 
clearly to distinguish, should also. be avoided : without attention to this, ob- 
servers might be employing different species, which would prevent the ge- 
neral operation from being comparative. ; 
Finally, all those flowers must be discarded, the zstivation of which does 
not admit of our accurately noting the exact moment of expansion: such as 
Calycanthus, Illecebrum, Aquilegia, &c. 
The table of species marked out for the daily observations has been formed 
from these considerations. In the construction of it our object has been to 
obtain results which might be useful at the same time to meteorology, to 
botany and to agriculture. With this view, we have aimed at representing all 
the families of the European plants, excepting those which do not contain 
plants fit for cultivation; this consideration is of great interest with regard to 
botanical geography. We have also introduced into it some North American 
genera cultivated in Europe, as the Catalpa, Tradescantia, Menispermum, &c., 
in order that this list may be rendered comparable with that of observations 
made in the United States of America. In each family we have selected in 
preference the most common and diffused species, and amongst them such 
species as have the flowers largest and best-developed. Finally, we have 
selected flowers so as to present some species which blossom in each month of 
the year. Amongst these plants are some which we especially recommend 
to the attention of observers, such as rye, wheat, the lilac, the box, &c.: 
these are distinguished by italics. 
The period at which rye, barley and winter wheat come into ear should 
be carefully. examined, this point being of great importance in agriculture. 
In the district of Tournay it is a farmer’s axiom that April is never seen to 
