212 Dr Daubeny on the Writings and 



tare, which are seen in species of plants belonging to the 

 same common type, as modifications produced by the causes 

 above assigned, just as the apparent irregularity of figure 

 which we observe in the same mineral had been referred by 

 Hauy to certain crystalUne laws acting upon molecules possess- 

 ing the same type. 



Moreover, a similar difference exists between the mode of 

 considering the organs of plants adopted by Decandolle, and 

 by antecedent botanists, as that which prevails between the 

 system of crystallography invented by the Abbe Hauy, and 

 that previously proposed by Rome de L'Isle. 



According to the latter, each crystal was viewed as in itself 

 a whole, possessing a certain definite figure, which was in 

 many cases modified by truncation, that is, by having its an- 

 gles bevelled off. 



According to the former, a crystal is an aggregate of a 

 number of molecules, possessing a particular figure, which, 

 clustering together in obedience to certain laws, produce a 

 variety of secondary forms, all, however, bearing some relation 

 to the primai'y one. 



So, according to the old mode of considering plants, the 

 corolla, the calyx, the seed-vessel, &c., was each considered a 

 simple organ, and the petals, the sepals, the carpels, &c. its 

 parts — whereas Decandolle regards each of the former as a 

 compound organ, and the latter to bear the same relation to 

 it, which the primitive molecules in Hauy's system do to the 

 crystals formed by their union. 



But the individual, to whom probably Decandolle was most 

 indebted for the germs of those opinions, which he has so 

 ably developed in his Theorie Elementaire, was his colleague 

 and associate, Lamarck ; and I could hardly fix upon any cir- 

 cumstance in the whole of his scientific career, more calcu- 

 lated to exalt his character morally as well as intellectually, 

 than the use he has made of the ingenious but fanciful views 

 which he obtained from this source, and the discrimination 

 which he exercised in separating the pure metal from the base 

 alloy. 



It is foreign to the objects of this Society to enter upon 

 any discussions connected with religion, nor indeed, if I were 



