416 Miscellaneous. 



patible with its beiug an embryo, and that it is more probable that 

 the enclosed skeleton is that of a small individual which had been 

 swallowed by the larger one as food. The specimen is in the Museum 

 at Geneva. — Yerhandl. tier Naturf. Gesellschaft in Basel, part vi. 

 p. 343, 1875. 



On the Periodical Movements of the Leaves in Abies Nordmanniana. 

 By M. J. Chatin. 



Abies Nordmanniana is a Conifer which is now widely diffused, 

 on account of the elegant coloration of its leaves, of which the lower 

 surface is whitish, while the upper surface is of a fine deep green. 



Now if this tree is obseiTed early in the morning, or in the de- 

 cline of the day, its foliage appears uniformly whitish ; but in the 

 middle of the day the green tint seems general. On attempting to 

 explain this difference of coloration, it is found to result from a 

 special position of the leaves, which varies during the day and 

 during the night : in the former case the leaves are spread out upon 

 the branch and present their upper surface, producing the greenish 

 aspect of the foliage ; during the latter period, on the contrary, it is 

 the lower surface that is presented to the spectator ; and this causes 

 the whitish tint of the Abies. 



Thus there is a diurnal and a nocturnal position. This merits 

 particular attention on account of the phenomena which cause it : 

 we see the leaves, which are at first horizontal, gradually erect 

 themselves upon the branch, so as to become often nearly 

 perpendicular to the branch ; but at the same time this movement 

 of erection is accompanied by a movement of torsion impressed upon 

 the basal part of the leaf, and which may frequently traverse an arc 

 of 90 degrees. In this respect the leaves of the upper branches seem 

 to undergo a sort of accommodation which enables this torsion to per- 

 sist in them, at least partially. This, however, is a peculiar fact 

 which I shall only indicate at present, with the intention of treating 

 it soon in more detail in another communication, in which I shall 

 have the honour of presenting to the Academy the results furnished 

 by experiments which will soon be completed, and which I have 

 undertaken with the object of ascertaining, in Abies Nordmanniana 

 and some other allied forms, the causes and mechanism of the pheno- 

 mena here mentioned, and the analysis of which enables me to exa- 

 mine, in their principal details, these movements of torsion, upon which 

 vegetable physiology possesses but few data. From another point of 

 view their study enables us to extend to the Gymnosperms the 

 existence of the spontaneous movements which old observers have 

 indicated in many Dicotyledons, which M. Brongniart has described 

 in several Monocotyledons, and which, as the present example clearly 

 shows, occur in the three great divisions of phanerogamous plants. 

 — Comptes Remlus, January 10, 1876, p. 171. 



