REVIEWS. ^ 345 



method. De Candolle's method with the Esogens is founded on the 

 idea of proceeding from the most highly developed forms in which 

 there is most multiplication and separation of the floral organs down 

 to those in which from union or abortion the structure of the flower is 

 apparently simplest. This is worked out by a quadruple division into 

 Snb'Classes or great sections having the following names and charac- 

 ters:— 1st. Thalamijlorce — petals distinct, stamens hypogynous, that 

 is to say, the several circles of organs springing from the receptacle 

 neither adhering together outwardly so that the stamens shonld seem 

 to arise from the corolla or calyx, or adhering inwardly, the calyx or 

 receptacle being attached to the ovary so as to place the fruit appa- 

 rently below the flower. 2nd. CalyciJlorcB — with petals distinct or 

 coherent, stamens perigynous or epigynous. 3rd. Corolliflorcs — having 

 a synpetalous corolla with hypogynous insertion bearing the stamens. 

 4th. MonochlamydecB — having a single envelope or no proper floral 

 envelope. That the series adopted by this great philosophical botan- 

 ist is not perfectly satisfactory need be no objection, since no series 

 can exhibit the real afiinities of organised beings. That his divisions 

 run into one another and are separated by very shadowy lines, leaving 

 us in doubt on which side we ought to place particular forms, is hardly 

 an objection since it is probable that no plan was ever devised to which 

 it does not apply ; but when we examine his arrangement in his own 

 philosophical spirit, under the guidance of principles which we have 

 learned from him, we cannot help seeing difficulties which it is, to 

 say the least, very desirable to overcome. It may be acknowledged 

 that the separation or mutual adherence of the circles of parts form- 

 ing the flower, depending as it does on the closeness of their origin 

 and the pressure to which they are exposed, is a valuable, and being 

 easily observed, a convenient character, so that, though not giving us 

 the natural classes which we earnestly seek, it deserves attention as a 

 source of sectional divisions, but when we look to the application of 

 the principle we find that whilst the hypogynose character distin- 

 guishes Thalamiflorse, Calyciflorte combines cases in which by outward 

 adherence the petals and stamens seem to be inserted on the calyx, 

 and those in which, the adherence being inward, the whole of the ex- 

 terior circles invest the ovary, a structure entirely distinct in its nature, 

 which is termed Epigynose, the other being Perigynose. It would 

 almost seem as if, adherence of circles being at all admitted as of im- 

 portance, the distinction of these two varieties necessarily followed. 



