VEGETABLE STRUCTURE. 7 



Rudolphi, Kaeser,* Dutrochet, and Amici, have pub- 

 lished very minute examinations of the Vegetable 

 Tissue, and accompanied them with dra^vings, both 

 numerous and accurate ; but the necessity of conti- 

 nually employing in these researches an instrument so 

 difficult to manage well as the compound microscope, 

 rendered abortive the dexterity of these observers : the 

 minute anatomy of vegetable structure is still, in the 

 more fundamental points, in a state of uncertainty dis- 

 couraging to the friends of the truth. " If any thing," 

 says Dutrochet, (Mem. Mus. 7, p. 385,) " can prove the 

 uncertainty of our information upon vegetable organiza- 

 tion, it is the difference of opinion existing amongst 

 naturalists upon this subject." There is, in fact, 

 hardly any point in vegetable anatomy, upon which we 

 do not mid that those who have devoted themselves to 

 it with the most care, are divided, not only upon the 

 theory, but even upon the facts, which one would think 

 observation should immediately decide. The contradic- 

 tions of observers of these points are so great, that it is 

 not an unfrequent occurrence for several persons view- 

 ing together the same fragment, with the same micro- 

 scope, to see, or to think they see, different appearances. 

 For a much stronger reason, are separate observers 

 unable to understand each other upon the most simple 



* Those who wish to study the elementary organs of plants more in 

 detail than the limits of this work have permitted me to assign to them, 

 will find an excellent review of this branch of the science in the Memoire 

 sur rOrganization des Plants, published by M. Kieser, (Haarlem, 1812, 

 1 vol. 4to.) This work contains a great number of well-observed facts; 

 and it is important to readers of French, inasmuch as it is the only work 

 written in this language which gives an idea of the labours of the Germans 

 in phytotomy. I regret much, myself, that my ignorance of the German 

 language has prevented me from studying these works in the original to 

 the extent which I should wish. I beg these learned men may be indul- 

 gent, if I have, contrary to my intention, either omitted to quote their 

 observations, or represented their opinions inaccurately. — A. P. De C. 



