52 SPREAD OF EVOLUTION. [1866. 



the sea ; for I could not resist, and I muddled my brains 

 with diagrams, &c., and specimens, and made out, as might 

 have been expected, nothing. Those angles are a most 

 wonderful problem and I wish I could see some one give a 

 rational explanation of them." 



To Dr. Asa Gray. 



May ii [1861]. 



" If you wish to save me from a miserable death, do tell me 

 why the angles of -, i, f, -f, &c., series occur, and no other 

 angles. It is enough to drive the quietest man mad. Did 

 you and some mathematician * publish some paper on the 

 subject ? Hooker says you did ; where is it ? 



To Dr. Asa Gray. 



[May 31, 1863?] 



" I have been looking at Nageli's work on this subject, and 

 am astonished to see that the angle is not always the same in 

 young shoots when the leaf-buds are first clistinguishable, as 

 in full-grown branches. This shows, I think, that there must be 

 some potent cause for those angles which do occur : I dare 

 say there is some explanation as simple as that for the 

 angles of the Bees-cells." 



My father also corresponded with Dr. Hubert Airy and 

 was interested in his views on the subject, published in the 

 Royal Soc. Proceedings, 1873, p. 176. 



We now return to the year 1866. In November, when the 

 prosecution of Governor Eyre was dividing England into two 

 bitterly opposed parties, he wrote to Sir J. D. Hooker : 



* Probably my father was think- These papers are mentioned in the 



ing of Chauncey Wright's work on Letters of Chauncey Wright.' 



Phyllotaxy, in Gould's ' Astronomi- Mr. Wright corresponded with my 



cal Journal,' No. 99, 1856, and in father on the subject, 

 the 'Mathematical Monthly,' 1859. 



