PHYTOGRAPHIC EXPRESSIONS AND ARRANGEMENTS. 201 



that at last we might complete the diagnosis of these minute yet 

 highly remarkable and not unimportant plantlets, although 

 Dr. Samuel Johnson, of last century's literary celebrity, would 

 very likely have relegated them to the division of useless plants as 

 one of the two into which he would wish the vegetable kingdom 

 apportioned ! 



As an instance of particular interest in Australia, how very much 

 the nomenclature of plants may become complicated, the genus 

 Persoonia may be adduced ; its earliest name is Pentadactylon — 

 bestowed exactly a hundred years ago by Gaertner in his celebrated 

 carpologic work, the pluri-cotyledonar structure of the embryo 

 having already been then so cleverly found out — but subsequent 

 researches proved, that this criterion applied to but few of the 

 many species of that genus besides the primary one, irrespective 

 of the fact, that an embryonic note is so little observable. Thus 

 then Gaertner's generic appellation was perhaps with injustice 

 discarded in favour of that of Persoonia ten years afterwards 

 established by Sir James Smith, who however missed to identify 

 it with Cavanille's genus Linkia, published and figured a year 

 earlier. Undoubtedly Persoonia should be changed into Linkia, 

 for although on chronologic reference the last mentioned name 

 will be found applied in 1805 also to Desfontainia, simply because 

 that genus is dedicated like Fontanesia to the same savant, yet 

 there is no valid reason for abolishing Delesseria, with a view of 

 keeping up a sole homage for Baron Benjamin de Lessert. Rules 

 of priority should also not be carried out injudiciously and 

 indiscriminately ; therefore it would be vain to re-establish the 

 name Lomandra for the genus Xerotes, inasmuch as that 

 designation was founded on a fallacious observation, the supposed 

 marginal attenuation of the anthers referring only to the 

 rudimentary stamens of the pistillate flowers. Names in Natural 

 History whether of plants or animals, cannot be arbitrarily 

 retained in some instances and changed in other similar cases ; 

 the rule must be uniform, and then only can it be just ; but the 

 etymology may be unalterably faulty, or the oldest appellation 

 may rest on erroneous or misleading ideas or on wrong geographic 

 record, while on the other hand the eldest name, as in the instances 

 of Bassia and Stylidium may simply have been missed by a very 

 pardonable oversight. 



Let us follow up some Australian data in this respect. 

 Limnanthemum stands in precisely the same relation to Villarsia 

 as Ipomcm aquatica to its other congeners. If Phebalium is to 

 be maintained, then Boronia, the next allied genus, needs to be 

 divided into two genera. If Euxolus is to be abolished, then 

 with Portulaca requires to be united Claytonia, a sub-genus of 

 Montia. Bassia has become restored recently also by Schweinfurth, 



