STUDIES OK THALICTRACEAE. — I. 49 



Studies of Thalictraceae. — I. 



It is not as the name of a suborder, or subfamily, but as 

 that of a proposed natural family of plants that I write 

 Thalictraceae. I have long carried in mind a conviction 

 that certain genera, Thalidrum heading the line, have not the 

 least natural affinity for, or genetic relation to Ranunculus , or 

 to Clematis, to Anemone, to Delphhihim, or to Paeonia. I do, 

 however, seem to see what to me are marks of real genetic 

 relationship among such genera as Thalidrum, Anemonella, 

 Isopysuni, perhaps Coptis, and more indubitably Aquilegia. 

 My own idea about a rather intimate relationship as subsist- 

 ing between the last named genus and Thalidrum found 

 expression many years since in my books of Californian 

 botany, wherein, removing Thalidrum afar from where all the 

 Jussieus, De Candolles, Benthams and Englers of a hundred 

 years and more had placed it, that is, on the Clematis side of 

 Ranunculus, I located it away on the other side, and in closest 

 juxtaposition to Aquilegia. I gave then no reasons for such 

 protest against fossilized artificialism, nor shall I give reasons 

 here. 



Thalidrum, itself falls into a number of groups so very 

 unlike each other as to flower and fruit that doubtless the time 

 is coming when segregate genera, a half-dozen of which have 

 already long since been proposed, will be freely admitted in 

 place of the conventional Thalidrum of the books that we 

 have. Such an event, when it comes, will accentuate the 

 demand for a recognized family of the Thalictraceae. 



Engaged seriously in the investigation of this aggregate 

 Thalidrum for now more than twenty years at intervals, I 

 have given a closer application to it during the last three years 

 than I ever gave to any other genus, but hitherto with but 

 few results that are to me quite satisfactory ; and I have come 

 to feel that it is the most difficult of all the phanerogamous 

 genera of the North American flora. Also I find no evidence 

 that other students of the group have even dimly apprehended 



I<EAFi,ETS, Vol. II, pp. 49-68. 29 March, 1910. 



