Dr. Schleiden on the Structure of the Ovule in Plants, 163 



ovarium uniloculare, ovulo pendulo in Viscum, or in Corylus 

 of an ovarium biloculare, ovulis initio erectis mox pendulis^ '^ 

 happily their disciples are kind enough to believe the teacher 

 upon his word, or otherwise they might easily devote their 

 life in vain to find such pretty descriptions confirmed by na- 

 ture. 



But if at last, and indeed with perfect justice, an essential 

 value has been placed on the description of the formation of 

 the ovule, and if we are every day more and more convinced 

 that a plant is not a crystal which can be laid aside today, 

 and ten years afterwards found in the same state, but that 

 engaged in constant, active, and lively development, it some- 

 times manifests this side of its life, sometimes that, and thus 

 every moment escaping the observer, it nowhere can be con- 

 ceived as a process terminated in a given moment, but solely 

 as the idea of several stages of development, and as the col- 

 lective expression of an uninterruptedly continuing process ; 

 then indeed it is evident that by the present mode of proceed- 

 ing science is not much advanced ; and that on the one hand, 

 a fixed moment must be established for the description of 

 the structure of the ovule according to Linnaeus's notions ; 

 but, also, on the other hand, that the progress of develop- 

 ment must be indicated, through which apparent differences 

 at certain periods may be reconciled with a higher unity, 

 while apparent resemblances are resolved into their proper 

 members according to the different principles of develop- 

 ment. Here again Robert Brown is the name which first 

 trod the right path and indicated what is required of us, al- 

 though, as in many other cases, without any one making use 

 of or following up his ingenious indications. Robert Brown, 

 struck by the apparent contradiction in finding in the same 

 genus {Euonymus) both pendent and erect ovules at the same 

 time, inquired further, and discovered the law, that the raphe 

 in the ovule constantly passes along the side directed towards 

 the placenta ; that in the ovula pendula oi Euonymus this is not 

 the case, but that they become ovula erecta, if in imagination 

 we again bring the raphe into the right position ; that there- 

 fore the ovules of this plant are only apparently pendent (pro- 



* Of course, ovarium in its stale at the time of flowering is here intended. 



