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BOTANICAL. 



Aspidium dumetorum — A species first proposed by our late President in the 

 4th volume of the English Flora. This is made up of two plants, the one from 

 Cromford Moor, being a dwarf state of A. dilatatum, and the other from Ravel- 

 ston Wood, near Edinburgh, having the segments of the frond abruptly trun- 

 cate, and the habit, at first sight, altogether peculiar ; but an inspection of the 

 original specimens in the Smithian herbarium proves it to be nothing more than 

 an accidental variety of the same species, namely, Aspidium dilatatum, arising 

 from disease, which is shown by the sudden termination of the costal, and by 

 the partial decay of the other segments. Specimens of the more ordinary state 

 of A. dilatatum, gathered at the same time and from the same locality, are simi- 

 larly affected, but in a less degree. The distinctions derived from the fructi- 

 fication in the English Flora are altogether fallacious, and are partly dependent 

 on the age of the frond, and partly on that of the individual plant. It is clear, 

 therefore, that the Aspidium dumetorum must be erased from the list of species. 

 — Don. Trans. Linn. Soc. Vol. xvii. Part iii. 



Asplenium Filix Fcemina — There are two very marked varieties of this plant ; 

 the one with broader segments of a dark-green, and with the stipes and rachis 

 of a pale-purple hue ; the other, and that the commonest, with the segments of 

 a more delicate texture, and the whole frond of a pale green. The latter variety 

 varies much in size, according to soil and situation ; in damp shady places it be- 

 comes the Filix fcemina of English botany, and in more open exposed situations 

 the irriguum ; but neither of these states is entitled to be regarded as a distinct 

 form. — Don. Trans. Linn. Soc. Vol. xvii. Part iii. 



Pilularia — In the last Number of the Magazine of Zoology and Botany, 

 there are some observations regarding Pilularia globulifera ; the author of them 

 states the absence of spiral vessels, and does not mention the occurrence of 

 vessels of any kind in the fibrous root of the plant. By careful and repeated 

 examination of the roots, slender creeping stem and leaves of Pilularia, I have 

 detected in each one of these parts a central fasciculus of ducts mixed with 

 spiral vessels, and after many attempts, I have succeeded in unrolling the spiral 

 fibre of the latter. This was effected by tearing the parts asunder by means 

 of fine needle points. It is necessary to do this in a drop of water and under a 

 high power of the microscope. Moreover, the parts must be previously mace- 

 rated in water during a considerable length of time. 



The presence of spiral vessels will thus strongly support Dr Lloyd's opinion, 

 viz. that Pilularia deserves to hold a higher rank in the vegetable creation than 

 has been supposed hitherto. With regard to Dr L.'s concluding remarks on 

 the circulation in Pilularia, they are not strictly in accordance with the opinions of 



