General Notices. 4l7 



Many of the sets buried 9 in. did not vegetate, or at least failed in reaching 

 the surface. This was also found to be the case by Hasler HoUist, Esq., in 

 1835, when he adopted the mode of deep planting. The results of his experi- 

 ments are detailed in the following note : — 



" ' I have this year renewed my experiments on the potatoes you sent me 

 in 1833 from Mr, Knight's collection. 



" ' I planted in the latter end of March, and at intervals during the whole 

 month of April, but I am satisfied I was, contrary to the received opinion, 

 too early in some instances, particularly with Mr. Knight's No. 2. 



" ' I also planted at various depths, 9 in., 7 in., and from 5 in. to 6 in. In 

 nearly every instance the shallow planting has succeeded, but in none the 

 deepest, and in the latter case many of the sets have not vegetated at all, 

 many more have not reached the surface. 



" ' A few single eyes of the Downton Yam, literally parings, have yielded 

 very nearly as much as the full-sized sets. I think I could say quite as 

 much if the tubers from which they were cut were added to their actual 

 produce. 



" ' Some of these statements appear so singular that I feel a hesitation in 

 mentioning ; them but, whether from the unfavourable season, mismanage- 

 ment, or what other cause I know not, certain it is, that these are my results. 



" ' P.S. The soil is a loamy sand, and friable.' " 



MISCELLANEOUS INTELLIGENCE. 



Art. I. General Notices. 



Influence of various Circumstances in the Growth of Plants in modifying their 

 Physiological Action. Extracted from a paper bj' Dr. Christison, read before 

 the Royal Society of Edinburgh, Feb. 3. 1840. — " The author commenced 

 with some remarks on the various causes by which the action of plants and 

 of their products on the animal body may be mo(hfied, and on the great vague- 

 ness and uncertainty of the information at present possessed in regard to the 

 influence of those causes which seem to arise in peculiar circumstances of 

 vegetation, more especially climate, weather, soil, and the progress of vegeta- 

 tion. He then stated the sources of information on these points ; namely, 

 the curative or therapeutic action of drugs on man^ their effects on the 

 healthy function, both of man and animals, either as medicines or as poisons, 

 their sensible qualities, and their chemical analysis ; and he assigned rea- 

 sons for discarding the first of these from the enquiry, and for trusting, in a 

 great measure, to the criterions derived from sensible qualities, from the eflFects 

 of poisons on the lower animals, and from chemical analysis. 



" The remaining part of the present paper was confined chiefly to the influ- 

 ence of the progress of vegetation on the activity of plants. Doubts were 

 thrown, by the results of his investigations, on most of the current doctrines 

 on this head ; but the present state of the enquiry did not lead to any general 

 inferences being drawn with confidence. 



" An extended statement was made upon the influence of the progress of 

 vegetation upon many of the active species of the natural family Ranuncu- 

 laceae. It was stated, that in the acrid species of the genera Ranunculus, 

 Anemone, and Clematis, the acridity, which is the same throughout them all 

 in quality, is possessed in nearly equal activity by the leaves, from an early 

 period in the spring until they are about to decay ; but that it exists in the 

 germens only while they are green, and disappears there entirely as the seeds 

 ripen. In the acrid species of Aconitura, the acridity of the leaves, on the 

 contrary, continues only until the seeds begin to form, and then gradually, but 

 quickly, disappears as they ripen, while the seeds acquire precisely the same 

 peculiar kind of acridity. The narcotic properties of the leaves, however, do 



