378 BOTANY [Chap. XI 



Letter 698 done. I think I cannot resist throwing the contrivances in 

 orchids into his teeth. You say nothing about the flowers 

 of the rue. 1 Ask your colleagues whether they know any- 

 thing about the structure of the flower and ovarium in the 

 uppermost flower. But don't answer on purpose. 



I have gone through my long Index of Gardeners 

 CJiro7iicle, which was made solely for my own use, and am 

 greatly disappointed to find, as I fear, hardly anything which 

 will be of use to you. 2 I send such as I have for the chance 

 of their being of use. 



Letter 699 To J. D. Hooker. 



Down, Jan. 16th [1869]. 



Your two notes and remarks are of the utmost value, and 

 I am greatly obliged to you for your criticism on the term. 

 " Morphological " seems quite just, but I do not see how I can 

 avoid using it. I found, after writing to you, in Vaucher 3 

 about the rue, but from what you say I will speak more 

 cautiously. It is the Spanish Chesnut that varies in diver- 

 gence. Seeds named Viola nana were sent me from Calcutta 

 by Scott. I must refer to the plants as an " Indian species," 4 

 for though they have produced hundreds of closed flowers, 

 they have not borne one perfect flower. You ask whether I 

 want illustrations " of ovules differing in position in different 

 flowers on the same plant." If you know of such cases, I 

 should certainly much like to hear them. Again you speak 

 of the angle of leaf-divergence varying and the variations 

 being transmitted. Was the latter point put in in a hurry to 

 round the sentence, or do you really know of cases ? 



Whilst looking for notes on the variability of the divisions 

 of the ovarium, position of the ovules, aestivation, etc., I 

 found remarks written fifteen or twenty years ago, showing 

 that I then supposed that characters which were nearly 

 uniform throughout whole groups must be of high vital 

 importance to the plants themselves ; consequently I was 

 greatly puzzled how, with organisms having very different 



1 For Rata see Origin, Ed. v., p. 154. 



2 For Hooker's projected biological book, see Letter 696. 



3 Plant es tt Europe, Vol. I., p. 559, 184 1. 



4 The cleistogamic flowers of Viola are used in the discussion on 

 Nageli's views. See Origin, Ed. v., p. 153. 



