582 EEPOET — 1882. 



1. Ordines Plantarum. 



Under this head I have no work of importance to bring before your notice. 



Indeed it is not to be expected that worts of this kind shoiild appear at more 

 than very rare intervals ; for not only do general treatises on the relationships of 

 natiu-al orders require for their successful treatment an intimate acquaintance with 

 veo-etable moi-phology, both gross and minute, but there must also be a special 

 acquaintance with the life-history of a large nxmiber of individual species belonging 

 to each order. And, moreover, this very extended knowledge (which is possessed 

 by few botanists) must be accompanied by an acutely logical mind and great 

 soundness of judgment. 



2. Genera Plantarum. 



For the same reason that works descriptive of the orders of plants appear but 

 rarelj', so are works descriptive of the genera of plants few and far between. 

 Indeed, where there is an attempt to describe all the genera belonging to the 

 Phanerognmia, such works are less frequent ; inasmuch as the mechanical labour 

 of dissecting the innumerable number of species of which the genera are composed, 

 and of writing out a description of them, is infinitely greater. 



I have, however, tlie great satisfaction of being able to record the near comple- 

 tion of that monument of original research and industry, ' The Genera Plantarum,' 

 by Mr. Bentham and Sir Joseph Hooker. This work, the publication of which 

 has extended over a period of exactly twenty years, consists of three large octavo 

 volumes, each of which contains over one thousand pages of closely printed matter. 

 In these pages are described the genera belonging to the angiosperms and 

 gvmnosperms, amounting in all to the enormous number of something like 7,400. 

 Simply to compile from works so large a number of genera would entail an 

 immense amount of labour. But when we know that each genus has been critically 

 investigated by one or other of the authors, not only as regards the characters, which 

 were to determine its limits and explain its affinities with other genera, but also as 

 regards its synonymy, which, in many instances, had become fearfully involved ; 

 and when we add to tlsis the Icnowledge that the geographical distribution of each 

 genus has been carefully worked out, we can only maiwel that so much should have 

 been done so quickly. 



No doubt, as time goes on, and new plants are discovered, and more complete 

 information is gained respecting old ones, it will be found necessary to revise the 

 characters and limits of some of the genera. And when all is done, there will be 

 diti'erences of opinion in many cases as to where the limits may be most conveniently 

 placed. Nevertheless, there can be little I'oom for not believing that , in by far the 

 greater number of instances, the genera as here defined will be accepted as fixed so 

 long as our present nomenclature exists. 



3. Species Plantarum. 



Under this head again, so far as the Phanerogamia are concerned, there is 

 nothing new to report. Nor do I think there is any likelihood that any general 

 work, including all the species which are known, will be forthcoming for many 

 years. Indeed, I do not feel sure that it wovdd be desirable at present that any 

 one should attempt such a work. And for the following reason. 



"Within the last few years, many parts of the world, which were foi-merly un- 

 known or closed to us, are begiiming to be thrown open to our collectors ; and we 

 have had already a large number of new species sent home. But in many of these 

 parts, our collectors have reaUy been able to do little more than snatch at the flora, 

 as they have hurried through on some rapid journey. Hence we may fairly expect 

 that for many years to come there will be more new species constantly turning up. 

 This being so, I think it might be better that we should wait a little longer till 

 the list of known plants approaches nearer completion. 



Meanwhile, there is a great deal of needful preparatory work, which is being 

 done ; such as the carefully comparing every new species with those already Imown, 



