Page:Journal of botany, British and foreign, Volume 9 (1871).djvu/29

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THE TRAKSPIKATION OF 'WATERY FLUID BY LEAVES. 19

say modified, inasmncii as in every case, the plants were obviously affected by a minute white fungns, to which the changes from the normal state were no doubt due. As I was obliged at the time to put the specimens in spirit for future examination, I can say nothing about the fungus itself; it may, perhaps, have l)een Uredo Candida, which ]\Iasters states (' Ve- getable Teratology,' p. 279; to be a common cause of Chloranthy in Cru- cifers. Similar monstrosities seem to have come under Dr. Masters's notice, but I think mine sufficiently interesting for detailed description. The lower part of the rachis was normal in its appearance in every case, and bore ordinary immature pods. The upper part, however, measuring about three inches more or less, was very much hypertrophied, being about half an inch in thickness ; all the flowers belonging to it were abortive. Where the hypertrophy had not been quite symmetrieal, the axis was a good deal curled and twisted. The most curious feature was the change produced in the flowers. In one instance there was a kind of corymb of chloranfhous flowers, each about half the natural size. In all the otiier cases, the flowers, with one, or very rarely two exceptions, were completely atrophied, while those which were not atrophied were very much hpyer- trophied, measuring quite an inch across. This kind of balance between the atrophy and hypertrophy is somewhat curious if we look upon the enlargements as due to the growth of a mycelium in the tissues. The pedicel of the enlarged flower was genei-ally about 1 m. long and ^ in. thick. The sepals were spreading, each oblong, about \ in. long, very fleshy,* and united at the base, occasionally forming a kind of dilated calyx-tube. The petals which, like the other parts of the flower were green, were twice their normal length, spathulate in form and with laciniale margins. The stamens in the flowers which were most symme- trically modified, were more or less distinctly eigJd and in two whorls, the outer opposite the sepals, the inner opposite the petals ; all were about the same length when equally developed. The anther was represented by a kind of hooded leafy appendage turned upwards with a short, thumb- like claw, projecting from the opposite side of the filament. The ovary was about an inch in length, but except for its enlargement and the thick- ness of its walls, not otherwise altered; the ovules were larger than usual, but immatru-e. — W. T. Thiselton Dyer.

��^dracts antr l^bstntcis.

��expeuiments on the transpiration of watery

FLUID BY leaves.

I

{From a Paper by TT. R. M'Nah, M.D. Edin., Professor of Natural His- tory Royal Ayricnllnral Colleyc, Cirencester, read before the Botanical Society' of Edinburgh, November lOth, 1870.)

The experiments detailed in this paper were commenced in August last, and continued during Septendjer and October. The author's inteu-

  • Dr. Masters states {I. c. p. 428) that the parasitic Fungi produce enlargement

of the perianth in Capsella Bursa-pastoris, DC., and other Cruciferm.

c 2

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