DISTINCT CENTEES OF CEEATION 473 



is right, and that there are not 50,000 species of flowering 

 plants known. WalHch has 8 names for Pteris aquilina, 

 and I do think he has two names for | of the species in the 

 early part of his catalogue, besides Don's, Koyle's, Edge- 

 worth's, Koxburgh's, and often De Candolle's. This how- 

 ever is an old story. I admire your great caution and 

 desire to curb my rabid radicahsm : but the tide will turn 

 one day and the reducing species will go on apace, and then 

 the reaction will be terrific. After all there is something 

 to be said for me. I am a rara avis, a man who makes his 

 bread by specific Botany, and I feel the obstacles to my 

 progress as obstacles to my way to the butcher's and baker's. 

 What is all very pretty play to amateur Botanists is death 

 to me. 



The following letters to Asa Gray deal with the Introduction 

 to the New Zealand Flora. 



Kew : Wednesday, January 26, 1854. 



My dear Gray, — I was extremely pleased by your letter 

 last night, and quite as much with the mere fact of my treating 

 of the subject having been thought worthy your attention, 

 as with the many too flattering things you say of it. Such 

 Essays attract so little attention in this country, that one feels, 

 at least I did, that I was writing for the dead more than for 

 the living, though amongst other men Agassiz had a promin- 

 ent seat in judgment before me. After all I regard the whole 

 Essay more as a resume of general impressions than a speci- 

 men of close reasoning, for of the latter, in truth, the subject 

 does not admit. There is not a single argument that will not 

 cut both ways, and may not be turned pro and con species, 

 specific centres, &c., &c. Your turning my arguments 

 against myself on the point, that two originally created dis- 

 tinct species so similar as to be almost undistinguishable, 

 may exist in two widely sundered locahties, is an awful 

 staggerer, and I have always felt it to be the most impractic- 

 able objection of any to the possibility of determining what 

 is and what is not a species. I have touched on that very 

 point at ch. 2, § 2i towards end. ' These considerations; etc.,' 

 but perhaps too gingerly, also in the Fl. Antarct. I think, see 

 Emyetrum. I combat this theory more upon principle than 

 upon facts ; — once admit it and the flood gates are opened 



