182 Dr. Schleiden on the Development of the 



In this manner an extravagant view has been thrust upon 

 the science, founded upon the weakest possible grounds, the 

 circumstance itself been loaded with difficulties, and the na- 

 tural condition most completely neglected. We shall see 

 further on how easy is the explanation of the only apparently 

 contradictory fact of the placenta parietalis, by the assumption 

 that the placenta is a formation of the axis [Axcngehilde\ which 

 indeed may be proved, without the assistance of hypothesis, 

 from the well-known modifications of the stalk. But if we 

 pass over to the investigation of nature, we find — to commence 

 with the most simple conditions — that each individual carpel- 

 lum is at first quite isolated, constructed similarly to every 

 young leaf or lateral organ of the plant. It is not until a 

 much later period of their development that it begins to di- 

 rect its edges inwards when the carpellum is closed, or to ad- 

 here to the neighbouring edges when the pistil is unilocular 

 and many-leaved. 



Amongst those families which in this respect again deviate 

 from the ordinary plan, must be included the Graminece and 

 CyperacecE. In both families their development shows that 

 the ovarium consists of 07ie carpel only. In both families the 

 two anterior* stigmata for the carpel are merely a further de- 

 velopment of the ligula ; the posterior, however, which is so 

 often abortive in the grasses, is analogous to the surface of 

 the leaf, and the ovarium itself to the sheath of the leaf. 



We can now take a reviev/ stage by stage of the entire de- 

 velopment of the pistil, from its first appearance as a flat foli- 

 aceous organ, until it becomes divided into ovary, style, and 

 stigma. This will enable us to obtain a correct idea of these 

 parts, for which little has hitherto been done, as organs whose 

 use and function, completely different, have received the same 

 name. 



The ovarium then is that portion of the leaf which incloses 

 the omda ; the style, that portion which is rolled up and does 

 not develop ovula^ whose object is to conduct the prolonga- 

 tion of the pollen tubes; and lastl}^, the stigma is the free termi- 

 nation of the superior part, whose object is to receive and hold 

 the pollen. 



This result is attended again with manifold consequences. 

 We find in the nomenclature of organs, for instance, that en- 

 tire families to which styles had been ascribed, as the grasses, 



gation of living nature as of the "physiological principles" paraded in the 

 title ; and the author shows himself to be at least thirty years behind the 

 most common-place botanical works of the present day, and even not au 

 niveau with such men as Grew and Malpighi. 

 * If the ovarium be viewed in a direction from the axis. 



