THE GENEBA PLANTAKUM DESCEIBED 23 



he considered the sequence best adapted for his purpose 

 that is the so-called Candollean. I am quite sure he had 

 no hypothetical view. 



Lastly with regard to the primitive Type of Angiosperms. 

 I am disposed to think that apart from Geological Evidence, 

 the channels along which this is to be sought have not been 

 explored, if found. 



An excellent description of the Genera Plantarum is given 

 by Professor F. 0. Bower, which I quote from ' Makers of 

 British Botany,' pp. 313-14. 



It consists of a codification of the Latin diagnoses of 

 all the genera of Flowering Plants. It is essentially a work 

 for the technical botanist, but for him it is indispensable. 

 Of the known species of plants many show such a close 

 similarity of their characters that their kinship is recognised 

 by grouping them into genera. In order that these genera 

 may be accurately defined it is necessary to have a precis 

 of the characters which their species have in common. This 

 must be so drawn that it shall also serve for purposes of 

 diagnosis from allied genera. Such drafting requires not 

 only a keen appreciation of fact, but also the verbal clearness 

 and accuracy of the conveyancing barrister. The facts 

 could only be obtained by access to a reliable and rich Her- 

 barium. Bentham and Hooker, working together at Kew, 

 satisfied these drastic requirements more fully than any 

 botanists of their time. The only real predecessors of this 

 monumental work were the Genera Plantarum of Linnaeus 

 (1737-1764) and of Jussieu (1789), to which may be added 

 that of Endlicher (1836-40). But all these were written 

 when the number of known genera and species was smaller. 

 The difficulty of the task of Bentham and Hooker was 

 greatly enhanced by their wider knowledge. But their 

 Genera Plantarum is on that account a nearer approach to 

 finality. Hitherto its supremacy has not been challenged. 



Notable in another way was the monograph on the strange 

 plant Welwitschia mirabilis, named after Dr. Welwitsch, who 

 had discovered it in Angola. Hooker did not do much in the 

 way of microscopic botany, but what he did was fifteen years 

 ahead of contemporary work, and remained of permanent value. 



