Botanical Collections, 



Mr Robert Brown has also recently publisTied some observations on these 

 pores, from which it is to be collected that, in the opinion of that distin- 

 guished observer, the stomata are rather of the nature of glands than of 

 pores, and are undoubtedly, in many cases, imperforate ; evidently having in 

 their disc a membrane, which is more or less transparent, sometimes opaque, 

 or very rarely coloured. The existence of colouring matter in the stomata 

 is the only circumstance that could have enabled an observer to prove their 

 imperforate nature ; for, in colourless membranes, such as those of Crinum, 

 in which the stomata are particularly large, the best microscopes, employed 

 under the most favourable circumstances, shew nothing but an apparent 

 orifice, closed up occasionally by the dilatation of two glandular bodies placed 

 beneath it. Mr Brown states, what was certainly a very unexpected fact, 

 that these bodies will often, in proteaceous plants, by their figure and posi- 

 tion, or magnitude, with respect to the meshes of the cuticle, determine the 

 limits, or even affinities, of genera, or natural sections. — Journ. of Royal 

 Inst. No. II. 



Smut in Corn. — This substance, which has been sometimes considered 

 a mere organic disease, but more usually a parasitical plant, analogous to 

 that which causes the mildew and the rust, and which has been described 

 under the names of Reticvlaria scgetum, Uredo segetum, and Uredo carbo, 

 has been lately the subject of a particular inquiry on the part of M. Adolphe 

 Brongniart, who thus describes the parts in which this malady is found, 

 and who adopts the opinion, that it is caused by the ravages of a kind of 

 fungus : — " The axis which supports the glumes and floral organs of grasses, 

 is formed of elongated cellular tissue, the cellules of which are placed close 

 together, without sensible intercellular passages, and of fibro-vascular 

 bundles of false tracheae or ducts, and spiral vessels : in the fleshy mass, of 

 which the smut consists, no structure of this sort is visible, at whatever time 

 it is examined ; but, for exatnining it satisfactorily, I have taken the plant 

 at the earliest period when the spike is capable of being examined. At this 

 time, the fleshy mass is found to consist entirely of an uniform tissue, con- 

 taining uniform four-sided cavities, separated by partitions, formed of one or 

 two layers of very minute cellules. These cavities, which, in organization, 

 resemble the regular lacunae, observable in the cells of aquatic plants, are 

 filled by a compact homogeneous mass, composed of very small granules, 

 perfectly spherical and uniform in size ; they were slightly adherent to each 

 other, and of a greenish colour, in spikes, but little developed ; distinct, or 

 simply clustered towards the centre of each mass, and of a pale nut colour, 

 in spikes which were a little developed ; finally, at a more advanced period, 

 the cellular partitions disappear, the globules separate completely, and the 

 whole mass is transformed into a cluster of powder, formed of very regular 

 globules, perfectly alike, black, and quite analogous to the reproductive 

 bodies of other fungi." — Ibid. 



Floral Organs M. Dunal, of Montpellier, has published two disser- 

 tations on certain organs of the flower, which, belonging strictly neither to 

 those which usually compose the calyx or corolla, nor to the organs of 

 reproduction, have been deemed anomalous, and given rise to numerous 

 botanical discussions. On the base of the divisions of the calyx, or the 

 sepals, he has observed in many flowers glandular organs of various forms, 

 which he calls lepals, because most commonly they appear in the shape 

 of small scales. Within these, that is, nearer the axis of the flower, he 

 distinguishes three series of organs very closely allied to each other, — 

 the petals, which alternate with the sepals, and two rows of stamens, 

 opposite to each other, alternate with the petals. Very often the stamens 

 have at their base a scale, which sometimes is attached to the filament, or 

 even closely united with it j and, on the other hand, the anther is, in certain 



