OBSERVATIONS ON THE GENUS PHYLLACHNE. 173 



plant along with its name. But even if the new rule became generally 

 accepted, it is little likely that this system of quotation would be 

 followed also. If we are to retain the binominal nomenclature, 

 botanists w^ill have to write Sjierriidaria diandra, Boiss. ; and if it 

 be desired to give additional information, it must be done by 

 appending synonyms [Arenaria diandra, Guss., S}}ergulana patens, 

 Hochst., &c.) Unless this be done, we are certain to find persons 

 writing the incorrect name, " Sjjergidana diandra, Guss." 



The only reason given in favoiu* of the new i^ractice by Mr. 

 Ball is that it w^ould be a less tax on the memory if the same 

 specific half were adhered to imder all generic changes. But the 

 argument is not a strong one. The whole question, it must be 

 remembered, is one for the close student of systematic botany only. 

 In the careful research which he must always make, he has less 

 occasion to draw^ largely upon his memory than to use his judgment 

 and his knowledge of bibliography. He aims at finality, com- 

 pleteness, and accuracy as to facts ; simplicity and freedom from 

 ambiguity in their expression. I think the new rule fails in 

 helping to secure any one of these. 



OBSEEVATIONS ON THE GENUS PHYLLACHNE. 

 By Baron Ferd. von Mueller, C.M.G., M.D., Ph.D., F.E.S. 



Some years ago I ventured to restore the genus Phyllachne 

 (* Fragm. Phytogr. Austr.,' viii., 39-40), it being established in 

 1776 by the Forsters, whereas the younger Linne, only four years 

 later, described the genus Forstera. The propriety of uniting 

 these genera was suggested already by Swartz, in 1790 (' Schrader's 

 Journal,' i., 273); but as at that time the laws of priority in 

 naming plants were not rigorously adhered to, Willdenow (Suppl., 

 iv., 148), in 1805, sacrificed the older name to the dictates of 

 friendship, and maintained that of Forstera for the united genera. 

 In this he w^as followed, as far as I am aware, by all subsequent 

 writers on the subject, except A. L. and Adr. de Jussieu (' Annal. 

 du Mus.,' xviii., 12, and 'Diction.,' v., 178), and Pfeiffer (' Nomen- 

 clat. Bot.,' ii., 691), until Mr. Bentham and Sir Joseph Hooker in 

 their ' Genera Plantarum ' severed again these two genera, Hooker 

 having some years previously established on some species of 

 Phyllachne his HelophyUiim (' Handb. of the New Zeal. Flora,' i., 

 167-168.) As the dehiscence of the fruit of these plants is one 

 only of degree, serving merely for sectional distinction, it must be 

 admitted that the generic separation rests mainly or entirely on 

 habit ; while that again is of no avail in the closely-allied Stylidium, 

 which is far more multiform in the external appearance of its 

 species than Phyllachne adopted in its widest limitation. Under 

 these circumstances, it is of particular interest to place on record 

 an additional Phyllachne, which introduces another kind of habit 

 into the genus, obliterating even to some extent the sectional 

 characteristics adopted for Phyllachne and Forstera. The plant in 



