35 



that circiiiatus and fluitaiis are now familiar to most botanists, 

 and that they are seldom confused with the other two unless 

 l)y beginners. But as to the limits and distinctions between 

 heterophyllus and pantothrix, or between the two groups of 

 Segregates into which they are cut Tip, these may still come 

 under the showman's liberally given choice to the childish 

 mitids, ' whieli you please, my little dears' "(p. 430). 



Whence, then, has Mr. Watson derived his present inspira- 

 tion ? It is from an elaborate paper of Mr. Hiern in the Journal 

 of Botany, February, 1871. 1.4i3051. 



He does not, however, take Hiern' s list in its entirety, but 

 gives a selection as far as he can understand the names ; and as no 

 descriptions could be given of the varieties retained out of 

 Hiern's 21, or reasons given for the omission of the rest, we are 

 left pretty much in the dark as to what is meant by the names 

 in the Catalogue. A reference to Hiern's own monograph will 

 not help us much, for he thus describes his method of determi- 

 nation : — " Each species is placed in a given plane with reference 

 to two axes of co-ordinates, the abscessa being the same number 

 of units of length as the normal number of Stamens, and the 

 ordinate being the number of veins on each petal. After being 

 placed in this manner, those numbered 1 — 5, Bab., lie in a 

 straight line whose equation is ^-4 y. +11=0. Those num- 

 bered 6-8, in a parallel straight line, whose equation is 

 t;-4 2/-f6=-0; and the remaining four, 9- 12, in a third straight 

 line, whose equation is a;-y=4. 



Let me give one practical comment on this learned trifling. A 

 large specimen of one of these forms of R. aquatUis was some- 

 what maliciously cut in two and submitted to one of these 

 " competent and judicious authorities." One of the two portions, 

 when retiu'ned, was found to be labelled radians, the other 

 Godroni. To be sure they are allowed, even at head-quarters, 

 to be only varieties of diversifolius ; but who can put much 

 faith in " varieties " after such a warning ? 



Some other sentences in the Compendium are so wise that I 

 cannot help quoting them : — 



