NA JURE 



577 



THURSDAY, APRIL 21, 1887 



GOEBELS OUTLINES OF THE CLASSIFICA- 

 TION OF PLANTS 



Outlines of Classification and Special Morphology of 

 Plants. By Dr. K. Goebel. A New Edition of Sachs's 

 "Text-boolv of Botany," Book II. Authorised EngUsh 

 Translation by Henry E. F. Garnsey, M.A. Revised 

 by Prof. I. Bayley Balfour, M.A., M.D., F.R.S. 

 (6.\ford : Clarendon Press, 1887.) 



LL botanists who have been familiar, since 1882, 



A 



with the original of this admirable work, will wel- 

 come the present translation, while it will be of even 

 greater value to the large class of students who were 

 unable to make use of the German edition. The full 

 importance of Prof. Goebel's work will only be realised 

 by those who have some acquaintance with the immense 

 progress made in the morphology of plants since 1S74, 

 when the last German edition of Sachs's " Text-book " 

 was published. Not a few of the most important of these 

 discoveries are due to Goebel himself, and this fact, no 

 doubt, partly explains the remarkable success with which 

 he accomplished the difficult task of re-writing Sachs's 

 Second Book. Goebel's work is, to all intents and pur- 

 poses, a new one ; but, at the same time, Sachs's own 

 words have been incorporated in the new text in every 

 case where the progress of the science did not actually 

 demand a change. 



Important additions to our knowledge have of course 

 been made since the first appearance of this work in 

 Germany. These have been duly recorded, in the Eng- 

 lish edition, by Prof. Balfour, who has wisely limited the 

 additions to foot-notes. In one or two cases it might, 

 perhaps, have been wished that these notes had been a 

 little fuller. 



It will not be without interest to enumerate some of 

 the more striking ditt'erences between this work and the 

 corresponding portion of Sachs's treatise. It must not 

 be forgotten that Dr. Vines's revised edition of the latter 

 work had already brought many of these points before 

 English readers. 



The same fourfold division of the vegetable kingdom 

 which was adopted by Sachs is maintained here, though 

 it is pointed out that a division into three (Thallophytes, 

 Archegoniatse, and Angiosperms) would be equally justi- 

 fied. The practical advantages of the former arrange- 

 ment are obvious. In the classification of the Thallo- 

 phytes we at once recognise a great advance. The 

 artificial " sexual system," as it has been called, is quite 

 given up, and an arrangement adopted which is based, as 

 far as possible, on the entire life-cycle of the plants in 

 question. Most teachers of botany will already have 

 long abandoned the groups of " Protophyta, Zygospores, 

 Oosporea:, and Carposporex-," but it will be an immense 

 gain to students to have a more natural system embodied 

 in a text-book. In Goebel's system we have five main 

 groups. Of these, the first two (Myxomycetes and 

 Diatoms) are kept separate from the rest, on the ground 

 of their uncertain relationships. Then we have the 

 Schizophytes, including the Cyanophycea or blue-green 

 Vol. XXXV.— No. 912 



.■\lgK on the one hand, and the Schizomycetes or Bac- 

 teria on the other. Then come the two main lines of the 

 Alga; and the Fungi, which are thus again recognised as 

 constituting natural classes, after the separation of the 

 lower groups above mentioned. 



The present arrangement is essentially that of De Bary, 

 and no one will doubt that it approximates as nearly to a 

 natural classification as our existing knowledge admits of. 

 The fact that the conditions on which Sachs based his 

 division have been repeatedly shown to vary among 

 the most nearly related plants, is sufficient proof of 

 the necessity for a return to less artificial views. It is to 

 be regretted that no satisfactory place for the Diatoms 

 has yet been found in classification. As regards the 

 Myxomycetes, it will scarcely be doubted that they have 

 no near relationship to any of the higher groups of plants. 

 The fact that the fusion of the plasmodia is not accom- 

 panied by a union of their nuclei shows that this process 

 cannot be regarded as a sexual one. 



It will be observed that the Yeast-Fungi no longer 

 appear side by side with the Bacteria, but are treated, 

 in accordance with De Bary's views, as reduced Asco- 

 mycetes. 



In the Algal series, attention may be called to the 

 interesting section on the Volvocineae, among which the 

 transition from zygosporous to oosporous reproduction 

 can be traced with special clearness. The discoveries 

 relating to Acetabularia, Dasycladus, &c., show that a 

 similar advance has taken place within the very distinct 

 group of the Siphoneas, while even among the simpler 

 Protococcaceffi indications of an external differentiation 

 between the sexual cells are not wanting. The account 

 of the Phaeophycea; is of special interest from the same 

 point of view, the series from Ectocarpus through Cutleria 

 to Fucus showing the passage from simple conjugation of 

 motile gametes to typical fertilisation of an oosphere by a 

 spermatozoid. 



The treatment of the red sea-weeds shows, on the 

 whole, a great advance, though we anticipate still greater 

 changes when the next edition comes to be written. We 

 may venture to express a doubt as to the view here 

 adopted, that the Bangiaceje are simple forms of the 

 Floridere. Schmitz has already shown how slight are the 

 grounds on which this arrangement is based. It seems 

 to us probable that a relationship of the Bangiaceae to 

 the Ulvacea may again be recognised in the future, as 

 has already been suggested by Mr. Bennett. 



The account of the Characeae is little modified from 

 that in Sachs, but it will be noticed that they are here 

 treated as oosporous Chlorophyceae. The question of 

 their systematic position will probably long remain 

 insoluble, but there can be no doubt that they have 

 little in common with any of the carposporous forms of 

 Algse. 



Among the Fungi many changes will be found, of which 

 only one or two can be referred to here. The gradual 

 progress of apogamous degeneration among the Perono- 

 spore and Saprolegnieae, so important for the whole 

 question of sexuality in Fungi, is fully described in the 

 light of De Bary's researches. 



Among other points, we may mention the advances in 

 our knowledge of the Lichens, especially of their repro- 

 duction, and also the view here adopted, that the Basidio- 



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