Vegetable Physiology for the Year 1836. 531 



much neglected. The Royal Society of Sciences of Gottingenj 

 sensible also of the defective state of our knowledge of vege- 

 table glands, has chosen this subject for a prize question, 

 which I have endeavoured to answer*. 



Griesselich names the oil-bearing glands which occur so 

 frequently in (not on) the substance of the leaves of the La- 

 biatte, pores; a term not particularly to be praised, as it might 

 cause a confusion of ideas, and, secondly, it must be placed 

 after those which we already possess. Together with Guet- 

 tard's denomination (glandcs vesiculates), the name, internal 

 glands, has been used by many phytotomists ; this is very pro- 

 per, and therefore should be retained, for this is the only kind 

 of compound glands which occur in the cellular tissue of 

 plants. Griesselich considers these inner glands as mere re- 

 ceptacles of a secreted substance, a view which is refuted by 

 the anatomical examination of them. What is said on the 

 occurrence of internal glands in Labiatce has already been 

 mentioned by Guettardf; nay, the latter has written much 

 more on this subject than will be found in the paper now be- 

 fore us ; unfortunately, however, Guettard's memoir has re- 

 mained almost unknown. 



JLabiatcc cultivated in gardens contain, according to Griesse- 

 lich's observations, fewer internal glands than wild species ; 

 this however can only relate to a smaller production of the 

 secreted oils; the glands are present in as large a number. 

 Guettard had already remarked, that in many of these plants 

 we could observe such glands in dried specimens which in a 

 fresh state exhibited none. 



Besides these internal glands, we find also external, but 

 simple glands, in the Labiata?, which I have mentioned in the 

 Gottingen prize essay. 



On the Reception of Sap, the Secretion and Nutrition of 

 Vegetables. 



Many very interesting experiments have been made on the 

 nutrition of vegetables; and it is to be hoped that we may 

 soon arrive at definite and generally received views on this 

 subject also. UngerJ for one, has given a very complete 

 enumeration and comparison of the experiments and views of 

 botanists and chemists who have treated on the reception and 

 the formation of the nutritive substance in vegetables. The 

 question, in fact, is, whether the vital principle of the plant is 

 of itself capable of forming the organic substances which serve 



* Meyen, On the Secretory Organs of Plants. Berlin, 1837. 4to. With 

 9 tab. of microscopical drawings. 



f Observations sur les Plantes. Paris, 1757- 2 vol. 8vo. 



% Influence of the Soil on the Diffusion ofPlants. Vienna,! 836, p, 125,&c. : 

 [See our present Number, p. 564. — Edit.] 



3 Y2 



