DESTRUCTIVE AND CONSTRUCTIVE TENDENCIES 469 



I showed him the Berberis which confounded him ; his 

 only objection (or crotchet) was the simple racemed form 

 of aristata, as different from the panicled form of the same 

 plant. These two he had studied living and found them 

 always distinct though growing side by side ; I showed him 

 loads of specimens he could not decide between ! but the 

 fact of his having found them distinct side by side outweighed 

 all others. Now what are we to give for such facts ? They 

 are most important, but are we to admit every collector's 

 (however good a botanist) testimony on such a point, as 

 of specific importance ? Thomson thinks lycium the only 

 good one on the same grounds, whereas Madden vows he 

 found these passing into one another every way. I took 

 asiatica for the best marked of them all, and that again 

 Madden denies in toto. I wish you would kindly tell me 

 what your own * particular variety ' was amongst them. 



In September 1853 he tells Munro : 



I am travailing through an Essay on ' Species, their 

 distribution and variation/ for the New Zealand Flora 

 Introduction [' which I hope;' he afterwards tells Bentham, 

 ' will be read, though I cannot flatter myself it will be of 

 any great use '], chiefly intended to open students' eyes to 

 the great leading facts of the case and to inculcate caution, 

 or they will have their Flora in a pretty mess, for it is a 

 frightfully variable one. 



But his apparently destructive tendencies were really con- 

 structive. He tells Harvey (January 1852) : 



I am combining very many species with Tasmanian and 

 South American plants many are identical without trace 

 of change, which led me to claim some variation for others 

 which belong to very widely different genera. . . . The up- 

 shot will be the total bouleversement of our previous ideas of 

 the extent &c. of the Flora and a very close alliance indeed 

 with Australia. I am really extremely anxious to get the 

 thing well done, but greatly doubt people's being satisfied 

 with my destructive propensities, which however are far 

 more really constructive than those who have few materials to 

 work from and judge by can form any idea of. 



VOL. I 2 H 



