August 27, 1903] 



NATURE 



;87 



and the information supplied by the collector regarding 

 them may be meagre. But Dr. Cooke, with his ripe 

 experience in India, is in a position of vantage. His 

 descriptions of genera and species are clear and vivid, 

 and at times include information on vegetative 

 characters that can be observed only on the spot. It 

 may be suggested, however, that an even more free 

 record of vegetative characters would greatly facilitate 

 the identification of a plant by a person happening to 

 meet with it in blossom but not in fruit, and would 

 supply botanists at a distance with valuable inform- 

 ation otherwise inaccessible. To take specific ex- 

 amples. The two indigenous lythraceous genera with 

 indefinite stamens, Lagerstroemia and Sonneratia, are 

 distinguished from one another in the analytical key 

 by their fruits ; yet their habits and habitats are 

 sufficiently dissimilar to be of immediate use in an 

 analytical key, but we are not told in the present work 

 whether or no Sonneratia apetala possesses the erect 

 respiratory roots so characteristic of S. acida. Again, 

 in the Rhizophoraceae, the four genera of the saline 

 swamps and littoral situations are at once separable 

 from the inland Carallia by their habitats, apart from 

 the seeds, which are used as the basis of distinction 

 in the analytical key. Furthermore, species of Rhizo- 

 phora emit aerial roots from their epigeous branches, 

 and thus stand apart from other rhizophoraceous 

 plants, and, indeed, so far as I know, from all man- 

 grove plants except Acanthus ilicifolius. Surely the 

 mention of these roots would greatly facilitate recog- 

 nition of species of Rhizophora, yet no mention is 

 made of them ; and if, as is quite conceivable, these 

 species are apt not to possess them in Bombay Presi- 

 dency, information to this effect would be of extreme 

 interest to botanists. Whilst discussing vegetative 

 characters, it may be remarked that the " white 

 spongy bodies " in the shoots of Jussiaea repens are 

 adventitious roots, not stipules. And the generally 

 accepted view in regard to the leaves of Rubia is that 

 they are stipulate, but that the stipules are often leaf- 

 like in form. 



Dr. Cooke's analytical keys of genera and species 

 are, it need hardly be stated, admirable examples of 

 the approved form, and he may be wise in adhering 

 to the system that experience has shown to be most 

 useful, even though it frequently assumes that a 

 person using the " flora " possesses shoots, flowers 

 and fruits of the specimen he desires to identify. 



The attractive and clear detailed descriptions of the 

 species are succeeded in most cases by mention of the 

 times of flowering. In many instances there is no 

 record as to whether a plant described is deciduous 

 or evergreen. Records on this point, coupled with 

 additional information as to the times of opening of 

 floral and vegetative buds, and of the shedding of the 

 leaves, would throw much light upon the scarcely 

 touched subject of the periodicity of plant-life in the 

 tropics. As this subject has, in addition, considerable 

 practical economic significance, it is to be hoped that 

 authors of the Indian " regional floras " will record 

 such of these data as are known, and will thereby 

 stimulate further observation. 



On the question of geographical distribution, facts 

 NO. 1765, VOL. 68] 



are given as to the occurrence of the indigenous species 

 in places outside the Presidency, and many details are 

 added concerning their frequency of occurrence, locali- 

 ties and habitats, within the Presidency. But the 

 author specially directs attention to the need for in- 

 formation on the local distribution of species. Despite 

 of this lack of complete information, the hope may be 

 expressed that Dr. Cooke will include in his work 

 some account of the floristic subdivisions of the Presi- 

 dency dealt with, and that the authors of other Indian 

 "regional floras" will do likewise. Of equal scien- 

 tific interest, and probably of greater practical im- 

 portance, would be an account of the distribution of 

 types of vegetation, or plant-formations, within the 

 area. Such an account of the distribution of types of 

 vegetation within Bombay Presidency would be of 

 especial botanical interest, for 



" the rainfall varies . . . from 3 or 4 inches, or even 

 less in the almost rainless districts of Sind, to upwards 

 of 300 inches on the Western Ghdts." 



The vegetation shows corresponding diversity, vary- 

 ing from arid or rocky desert-tracts to moisture-laden 

 evergreen forests. As to the practical aspect, we now 

 recognise that vegetation reflects in its form the 

 environment, and that plants, when their actions are 

 interpreted aright, are more cunning analysts of ex- 

 ternal conditions, including soil and climate, than are 

 the most accomplished chemists and meteorologists. 



Brief references to the economic uses of many of 

 the species described, and vernacular names, add value 

 to the book before us. 



In conclusion, Dr. Cooke is to be congratulated on 

 producing a most excellent work. 



Percy Groom. 



THE STUDY OF FERMENTATION. 

 Fermentation Organisms, a Laboratory Handbook. 

 By Alb. Klocker. Translated from the German by 

 G. E. Allan, B.Sc, and J. H. Millar, F.I.C. Pp. 

 XX + 392, (London: Longmans and Co., 1903.) 

 Price 125. net. 



THE importance of a systematic study of the micro- 

 organisms which play a part in the various pro- 

 cesses of fermentation is making itself felt more and 

 more as time goes on and new facts and phenomena 

 are brought to light. The old empirical methods of 

 twenty years ago have passed away before the marvel- 

 lous changes first introduced by Hansen, and the 

 culture of yeast is recognised as one of the secrets of 

 success in the manufacture of the various kinds of 

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 under some form of personal supervision. As in other 

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 method of teaching, and we have in this volume a 

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 in the culture of fermentation organisms to be more 

 widely spread, and probably more successfully con- 

 ducted, than has hitherto been the case. The volume 

 is welcome on this account especially, but it has other 

 claims also on the student, coming as it does from the 



