NEvV ORGAN I'A SEFDS. Q\g 



^' ters, Vv'li-ioh commonly strain the moisture like a very fine 



** cotton, it woviid jjeii.h, f.om being unabie to feed ou too 



" gross aliiuent," It i ; easy to perceive by t\\\6 passage, 



that Grew coatradicts biiiiself, and ttuit, adndlting with 



more reason the use of the coats, wliich be Vvvry ing-eiisously 



coiTipares to Hlters, he entirely rejects his iifft opinion of the 



functions of the micropyle. 



This learned finaton.ist, having- observed the micropyle He like-.vise 



Ouly in a 'jniail number of iet;iimi:ious seeds, in which this ^"P'"**^^ " ^^"■ 



• 1 1 I • 1 • /• 1 1-1 lorded a pas- 



organ IS constantly placed opposite tlie pouit or tl^e radicle, s.\>re to the ra- 



had imagined, tliat it likewise served lo afford this a passage ^'^^le. 

 in the process of germiiiatioa. Bnt how is it to be con- This jmproba- 

 c«:fiv^ed, that a radicle twenty or thirty times as large as tlie ^^^ ,^'°"* ^** 

 aperture of the micropyle can is^uo through it ? Besides, * 



:'.vhere is the person, that has ever had an opportunity of see- 

 ing a seed in the state of germination, who lias not observed, 

 that the radicle never emerges fi'om its captivity, till the 

 coats, being unable longer to contain the embryo, regularly 

 burst, and thus give a passage first to the radicle, and af- 

 terward to the entire young plant? If on the other hand we 

 add to this refutation, that, in a considerable number of and the flexion 



seeds, the interior membrane describes a quarter of a circle ''^ T°"/ '^^' 

 ' . _ _ ^ _ quire in some 



round itself in the outer integument, as in the commelina cases, 

 and tradeicantia, or a semicircle, as in the eyebright, louse- 

 wort, and cow-wheat, we shall plainly perceive, that the 

 micropyle of the interior membrane, to which the point of 

 the radicle answers, must be a quarter of a circle distant from 

 the outer micropyle in the former, and half a circle in the 

 latter ; and that from this construction it woizld be impossi- 

 ble for the radicle ever to issue by this aperture, since for 

 this purpose it must wind between the two coats, to come 

 out at last through the external micropyle, which in seeds 

 of this kind is always opposite to the micropyle of the inner 

 membrane, and to the radicle, which is inseparable from 

 the latter. 



If I have been so fortunate as to make known the true A new law in 

 way of fecundation in the ovula of vegetables, this is not ^'^®. ^*^'^"^^ **^ 

 the only advantage, that vegetable physiology will derive ' , 

 from my labours ; for the dissections I have been obliged to 

 make, to generalize the presence of the micropyle in all 



seedt. 



