PERIODICAL PHA NOMENA OF ANIMALS AND VEGETABLES. 321. 
Report of the Committee, consisting of Prof. OwEn, Prof. E. Fores, 
Dr. Lanxestser, Mr. R. Tayztor, Mr. Tuompson, Mr. Bau, 
Prof. Autpman, Mr. H. E. Srricxianp, and Mr. Basineton, 
appointed for the purpose of Reporting on the Registration of Pe- 
riodical Phenomena of Animals and Vegetables. 
Tue duty assigned to your Committee being to consider and report on the 
best means of concurring in the system of simultaneous observation of the 
Periodical Pheenomena of Organized Beings adopted by the Belgian and other 
continental naturalists, as proposed on their behalf at the Meeting of the 
Association at Plymouth, by M. Quetelet of Brussels, the Committee have 
judged it best, as a preparatory measure, to recommend to the Section D. 
(Zoology and Botany) to cause to be translated, and circulated among such 
naturalists as might be willing to give their assistance, the Instructions pub- 
lished and acted upon for a few years past by the continental naturalists 
above mentioned. 
The translation having been revised and enlarged with the aid of the Rev. 
L. Jenyns and M. de Selys-Longchamps, it is proposed by the Committee, 
' that copies should be circulated where they may be useful, in order to invite 
and facilitate the co-operation of observers in various departments of natural 
history. 
} 
INSTRUCTIONS FOR THE OBSERVATION OF PERIODICAL 
PHENOMENA. 
Royal Academy, Brussels. 
_ Wuitsrt the earth performs its annual orbit, a series of phenomena is un- 
_ folded upon its surface which the periodical return of the seasons regularly 
brings back in the same order. These phenomena, taken individually, have 
engaged the attention of observers in all times; but to study them as a whole, 
and to aim at ascertaining the laws of dependence and relation that exist be- 
_ tween them, have been generally neglected*. The phases of the existence 
: of the minutest plant-louse, of the paltriest insect, are bound up with the 
phases of the existence of the plant that nourishes it; this plant itself, in its 
_ gradual development, is in some sort the product of all the anterior modifica- 
j tions of the soil and atmosphere. That would be a most interesting study 
which should embrace at once all periodical phenomena, both diwrnal and 
annual ; it would form of itself alone a science as extended as instructive. 
~~ 
* There are doubtless few naturalists who have not collected some observations upon 
_ periodical phenomena; but the greater part of their labours, from their being isolated, would 
he nearly useless for the object which-we propose to accomplish. The various calendars and 
dials of Flora have been framed upon local observations, or such as, being made at different 
epochs and under circumstances entirely dissimilar, could not be compared with one another 
‘Ror present that degree of exactness which science demands at the present day. The great 
_Linnzus was fully aware of the utility to be derived from simultaneous researches on the 
calendar of Flora, and considered that, if made in different countries, a comparison of them 
; would be followed by advantages as novel as unexpected. It is, then, this idea of the cele- 
_ brated Swedish naturalist that we would wish to see realized, The United States of America 
_ seem to be the country which has most fixed its attention upon such a system of simulta- 
4 heous observations: the annual reports of the governors of the University of New York, 
_ printed at Albany, regularly contain observations from thirty places on the flowering and 
_ fructification of certain plants, on the arrival and departure of birds of passage, and on other 
“natural epochs. 
_ It would not be possible to specify here all the observations of this kind which have hereto- 
_ fore been undertaken ; even those made in Belgium by M. Kickx, sen. for 1811 (Flora Brux.) 
and by Messrs. Pollaert and Dekin (Alman. du départem. de la Dyle, an. xii.), or those of our 
_ habitual correspondents, Baron d’ Hombres Firmas (Rec. de Mém. et d’ Obs,, &c., Nismes,1838), 
Dr. Th. Forster (The Perenn. Calend., Lond, 1824), &c. 
mm 1845. x 
