28 The Ottawa Naturalist. [May 



To most botanists of this generation the name T. Cornuti 

 is unfamihar. They meet with it nowhere in the newer books but 

 in synonymy; and in the older herbaria they are apt to find it 

 erased, and the name T. polygamum written in its stead. It had 

 been in constant use among Am.erican botanists for more than 

 a century when, late in the nineteenth century it was remanded 

 to synonymy b\' Asa Gray. The condition of m.eadow-rue 

 nomenclature was not thereby improved, for T. polygamum had 

 been from the first a nomen nudum, that is, it had been printed 

 in a catalogue, v. ithout any accompanying description. All that 

 Dr. Gray was able to cite by way of diagnosis was "smooth, 

 polygamous;" so that any kind of Thalictrum showing glabrous 

 herbage and a tendency to polygamy would have to be T. 

 polygam,um. Yet despite all this, the author at once began to 

 include in his own T. polygamum. plants glabrous and plants 

 pubescent, and that in several different Avavs. They who use 

 the name T . polygamun use it on the mere dictum of authoritv. 

 There is less reason for it than for the old name T. Cornuti. Yet 

 even Muhlenberg, the inventor of the vacuous name T. poly- 

 gamum,, had admitted T . Cornuti, holding T . polygamum, what- 

 ever that may have been, to be distinct from it; thus by no 

 means intending to make a name that should be substituted in 

 place of T. Cornuti. 



The discoverv of the invalidity of the name T. Cornuti was 

 not made b}^ Dr. Gray. That point had been made clear 

 by Augustin Py ramus De Candolle away back in 1818, long 

 enough before the time of Gray; and De Candolle, suppressing 

 the unauthenticated T. Cornuti, gave a new name, and 

 therewith a description that is intelligible. I do not think 

 I can do students of Canadian Thalictums a better service here 

 than to give them an English ^'ersion of De Candolle's descrip- 

 tion; for the author savs that his specimen was from Canada. 



"Thalictrum corynellum. Stem erect, terete, finely 

 striate, hollow; leaves twice or thrice ternately divided, the 

 segments oval, at apex obtusely 3-lobed, otherwise entire, upper 

 face dark green, the lower glaucous, and beset with scattered 

 hairs, especially on the veins and veinlets; panicle erect, sub- 

 corymbose; flowers dioecious erect; sepals oval; filaments clav- 

 ate at summit ;anthers oval-oblong; fruits 12 to 15, sessile, striate, 

 oblong." [A. D.C. Systema, I. 1^2, 173]. 



M. De Candolle drew up the description from herbarium 

 specimens. He does not seem to have known that the filaments 

 are white. Thev seldom remain so in old specimens. The 

 specimens were in the herbarium of Vaillant, and the plant was 

 from Quebec, by Sarracenius. It is to be noted that he supposed 

 the species to be dioecious; and so it is, in the main. Rarely 



