4 86 



NATURE 



{Sept. 20, 1883 



fewer than 10,000 species. To assign definite generic 

 characters to a series of forms so closely allied was an 

 undertaking which, in spite of the previous labours of 

 many eminent botanists, required the most careful exami- 

 nation of an almost overwhelming mass of materials, 

 along with the severest critical acumen. The second 

 portion of the second volume includes the great mass of 

 the Gamopetalous families. At this period the pressure 

 of official duties, and those devolving upon him as Pre- 

 sident of the Royal Society, prevented Sir J. Hooker from 

 devoting much of his time to the laborious tasks of critical 

 systematic botany ; and to this portion of the work 

 he contributed only the allied families of the Vacci- 

 niacecs, Ericacece, and Epacridece, in addition to the 

 Myrsinece, Priiniilacea, and a part of the Sapotacea. 

 On Mr. Bentham devolved all the remaining families of 

 this vast group ; and to show the prodigious amount of 

 labour accomplished by this remarkable man, it is suffi- 

 cient to say that, along with minor families, these included 

 the Apocyiiccr, Asclepiadea, Gentianea, Boragineoe, Con- 

 volvichuea, Solanea, Scrophularinem, Gesneriacea, Big- 

 noniacece, Verbenaceee, and, finally, the Labiates. Some 

 additional years might have been requisite for such an 

 undertaking if his classical monographs on the two great 

 families Scrophularinea and Labiates had not supplied 

 Mr. Bentham with the materials for his subsequent work. 



The first part of the third volume is occupied by the 

 Monocklamydecs and the Gymnosperms. To this part the 

 group of the Curviembryece, including the important 

 families Amarantacea and Clienopodiacea:, was contri- 

 buted by Sir J. Hooker, who further undertook the Ne- 

 penthacecs, Cytinacece, and Balanophorecs. The materials 

 for the latter were ready to hand, being for the most part 

 contained in the remarkable monographs long since pub. 

 lished by himself. The remaining families of Mono- 

 chlamydecB were elaborated by Mr. Bentham. Amongst 

 the more important must be mentioned the Laurinetz, 

 Proteacecr, Thymelcsacea, and Santalacecs. But it was 

 especially the great families Euphorbiacea and Urticacece 

 which, in spite of recent monographs, demanded a vast 

 amount of minute examination and careful revision of all 

 existing sources of information. The Gymnosperms had 

 originally been undertaken by Sir J. Hooker, who 

 possesses so wide an acquaintance with these plants in 

 the living state ; but the pressure of other occupations 

 again interfered, and this group was also executed by 

 Mr. Bentham, doubtful questions here as well as through- 

 out the entire work being reserved for discussion between 

 the joint authors. 



The second part of the third volume, which concludes 

 the work, contains all the families of Monocotyledonous 

 plants. The examination and revision of the vast store 

 of existing materials appeared to the authors such a 

 formidable task that, in the doubt whether they should 

 be able to complete it, they resolved to attack in the first 

 instance the most difficult families, Sir J. Hooker under- 

 taking the Palms, and Mr. Bentham the Orchidetz. As is 

 well known, the study of these families offers peculiar 

 difficulties. In the former the great size of all the parts, 

 as well as their texture, usually makes it impossible to 

 preserve herbarium specimens available for study, and 

 much restricts the supply of materials to be found even 

 in the best-furnished museums. Notwithstanding his 



very extensive previous knowledge of this family, and the 

 exceptional resources available at Kew, Sir J. Hooker 

 found the task to involve a much greater expenditure of 

 time and labour than he had anticipated, chiefly owing to 

 the necessity for a very extensive correspondence with 

 botanists in various parts of the world who were able to 

 supply special information or materials not otherwise ob- 

 tainable. Along with other special difficulties, the study 

 of the vast family of the Orc/iidecs is hampered by the 

 unsatisfactory condition of a great proportion of the 

 specimens sent to Europe from countries whose climate 

 makes their preparation and preservation almost un- 

 manageable. It is not surprising that Mr. Bentham 

 found more than a year of unbroken persistent labour no 

 more than sufficient for this family, and that he subse- 

 quently required an equally long period in dealing with 

 the Graminees. 



In treating the remaining Monocotyledonous families, 

 the task of the authors was in many cases lightened, 

 though not by any means replaced, by the work of various 

 recent monographers. Sir J. Hooker disposed of the 

 group of Nuaiflorec [Aroidece and allied families) and that 

 of the Apocarpca, including the Triuridece, Alismacece, 

 and Najadea. To Mr. Bentham fell the heavy task of 

 completing the work by the examination of the numerous 

 remaining families of Monocotyledons, among which may 

 be specified the Bromeliacecs, Iridice, Amaryllidece, 

 Liliacca\ Commelynacece, Pandanece, Restiacecs, and 

 Cyperacccs. It is a surprising proof of exceptional 

 mental and bodily activity that in dealing with this por- 

 tion of the work, and in studying natural families where 

 the floral parts are too often lost or obliterated in dried 

 specimens, and therefore demand the most delicate and 

 careful dissection, Mr. Bentham, in spite of his advanced 

 age, revised and defined in the course of three years more 

 than 1200 genera. 



Throughout the progress of the work, as well as in 

 determining its original plan and arrangement, every 

 important question was decided after joint consideration 

 and discussion. In this way the limits and characters of 

 the larger groups, the descriptions of the natural families, 

 their subdivision into suborders and tribes, and the 

 arrangement of genera, were settled by mutual inter- 

 change of views. Almost invariably the work of each 

 author was read and criticised by the other before it 

 was sent to press, and the proofs were regularly cor- 

 rected by both, so as to eliminate as far as possible any 

 chance of divergence of opinion ; and, finally, they were 

 fortunate enough to obtain the help of a highly competent 

 friend, the Rev. M. J. Berkeley, who undertook the re- 

 vision of the Latin text with a view to secure the desirable 

 uniformity of style and diction. 



The descriptive characters of the families, or natural 

 orders, are drawn up with the same care as those of the 

 separate genera ; they are clear, exactly comparable, and 

 the affinities of families, as well as the exceptional and 

 abnormal forms which they not seldom present, are 

 specially noted. The approximate number of known 

 species belonging to each family, as well as to each 

 separate genus, is stated throughout the work, and the 

 geographical distribution of each genus, as well as of the 

 larger groups, has been recorded as fully as the present 

 state of our knowledge makes it possible. Finally, very 



