87 



On the Yellow Juice of (Enanihe crocata. By J. H. Balfour, M.D. 

 Professor of Botany in the University of Glasgow. 



In the last number of the ' Phytologist,' I observe that there is a 

 question put by Mr. Mill, as to the yellow juice of Qinanthe crocata, 

 (Phytol. ii. 48). 



It is quite true that on cutting across the roots of Q^nanthe crocata 

 in the fresh state, there is no appearance of a yellow juice ; but after 

 short exposure to the air and absorption of oxygen, I have frequently 

 seen the juice assume a yellowish or brownish tinge. In this way we 

 may probably account for the statements made by different botanists. 

 As to the acrid nature of the juice, I cannot speak from personal ob- 

 servation. 



It is curious to remark, in regard to the roots of this plant, that in 

 some localities they seem to be innocuous, while in others they are 

 decidedly poisonous. This has been distinctly shown by the experi- 

 ments of Prof. Christison. The juice of the roots of plants growing 

 in the neighbourhood of Edinburgh, had no effect when given in large 

 quantities to animals; while that from the roots of plants growing near 

 Liverpool, acted as a poison. Peculiarities of soil or climate would 

 appear to modify, in a remarkable degree, the properties of many re- 

 puted poisonous plants. Dr. Christison read an interesting paper on 

 this subject before the Royal Society of Edinburgh, and he has illus- 

 trated it by reference to CEnanthe crocata, Cicuta virosa, and other 

 plants. J. H. Balfour. 



11, West Regent St., 



Glasgow, Feb. 7, 1845. 



Observations on the Genus Ruhiis. By T.Bell Salter, M.D., F.L.S. 



At the close of ray remarks on the Botany of Selborne (Phytol. i. 

 1132), I forebore to make any comments on the Rubi I had obtained, 

 not, as I then observed, because they were either few, or wanting in 

 interest, but because they were still sub judice. Since that time I 

 have carefully examined them, and under circumstances, as I shall 

 presently show, which will enable me to speak of them with some 

 considerable degree of confidence. 



The genus Rubus had uniformly, and as if by common consent, 

 been neglected by the earlier botanists. With regard to the investi- 

 gation of our British species, nothing had been done until Bicheno 



