162 Dr. Schleiden ow the Structure of the Ovule in Plants. 



XVII. — On the Structure of the Ovule in Plants, By M. J. 

 ScH LEIDEN, M.D._, Professor of Botany in the University 

 of Jena*. 



LiNN^us established a fixed period for the description of the 

 organs of reproduction ; namely, for the floral organs the fully 

 developed flower at the moment of the diffusion of its pollen; 

 for the fruit, on the other hand, the moment of maturity, L e, 

 in general, the natural separation of the fruit from the plant ; 

 and in so doing he was perfectly right. Linnaeus undoubtedly 

 described well, for what he could not see with the naked eye 

 or with a moderate lens he passed over in silence. But it was 

 soon felt requisite to pay attention to parts not perceptible 

 to the naked eye ; and more especially since a preference has 

 been given to the natural arrangement of plants has it been 

 found necessary to take into consideration the structure of the 

 ovule. Now-a-days, indeed, it is pretty generally the case 

 that but few physiological botanists take the trouble to in- 

 quire into the structure of the ovule and the development of 

 the seed, and the more systematic botanists borrow their 

 statements upon trust and faith, or without such warrant 

 judge of the structure of the ripe seed, mutato nomine, from 

 the ovule f. He, however, who is not totally ignorant of the 

 history of the development of plants knows very well that the 

 gradual changes resulting from progressive development are 

 frequently so considerable, that even the reduction of later 

 stages to the earlier ones which have been actually observed 

 is quite impossible without constantly foUomng the progress 

 of development. Thus it seems singular enough, when de- 

 scribers with an air of great seriousness, as if they had ac- 

 tually observed it with their own eyes, talk for instance of an 



[» Translated from Wiegmann's Archiv, p. 282. Part IV. 1839. We 

 here beg to acknowledge our thanks to the author for the kind communi- 

 cation of separate copies of this and other interesting Memoirs. — R. T.] 



f That frequently accident or fancy have the principal share, is among 

 other things proved by the position of the Nymph(Eacece in Kunth's excellent 

 * Flora Berolinensis/ otherwise entirely arranged from personal and new ob- 

 servations. That in such a work the Nymphaacece should be classed under 

 Monocotyledons, and indeed, as Butomeis proxime affinesy and that the re- 

 searches of Brongniart, Mirbel, Brown, and Lindley should be entirely 

 passed over, is scarcely conceivable. 



