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REVIEWS. 



A Monograph of the Genus Sabicea. By Herbert Fqller 

 Wernham, D.Sc, F.L.S. 8vo, cloth, pp. 82, with twelve plates 

 and text-figures. Price 6s. London: British Museum. 1914. 



When volume iii. of the Flora of Tropical Africa appeared 

 (1877), the genus Sabicea comprised nineteen species, a number 

 gradually increased until, with the publication last year of the Cata- 

 logue of the Talbots' Nigerian Plants, forty-four species had been 

 described. It speaks well for the thoroughness of Dr. Wernham's 

 research that he has detected no fewer than sixty-two additional 

 species, thus making the total number known to-day a hundred 

 and eight. This result is embodied in the excellent monograph 

 with its twelve well-executed plates now lying before us. 



The nineteen pages of introduction are full of interesting 

 reading, and, provided the author's views on the derivation of the 

 various groups are regarded as suggestions merely as to what 

 may have happened — and this is all that is claimed for them — it 

 must be admitted that they are plausible and preferred with much 

 ingenuity. The main grouping of the species is founded upon the 

 inflorescence, the earliest form of which the author supposes to 

 have been the open cyme, from which has been derived the 

 condensed head, and finally the head surrounded by an involucre 

 of bracts. The difficulty in this matter of descent is that we do 

 not know whether unchecked advance from the simple to the 

 more complex really has occurred in the history of any group of 

 organisms. Thus, to take one case — a case with direct bearing, as 

 it happens, upon the point in question. The head of Composites 

 is allowed by all to be the highest expression of effectiveness in 

 floral arrangement ; yet there are genera, undoubtedly derived 

 from GompositcB of normal type, in which the head is reduced to 

 two or three florets, or even a single floret in a scattered inflores- 

 cence, thus harking back to a very primitive state of things. The 

 truth is, we know little at present about the phylogeny of 

 Angiosperms, and still less about that of their genera and species, 

 and so far ontogeny cannot be said to have proved of much use in 

 enlightening our ignorance. This, however, should not deter 

 monographers from giving us their conclusions, for speculation 

 can do no harm, provided its true nature be kept in view. 



Dr. Wernham's key has been carefully constructed, and the 

 species should be easily recognisable from it. We notice, too, a 

 very good point, one unfortunately not always present in recent 

 monographs, viz. the citation of the herbaria where the various 

 species may be found. We cannot, however, refrain from mention- 

 ing that in some cases the full nomenclature has not been given. 

 For instance, a Brazilian plant was considered in the Phanerogamic 

 Botany of the Matto Grosso Expeclition to be conspecific with 

 S. novo-granatensis K. Schum. Dr. Wernham finds this to be a 

 mistake, and he describes the plant under a new name without 

 reference to the erroneous identification. This is, however, 

 scarcely a matter of primary importance, and we may hope 



