The Evolution of Fruits. 13 



the various apocarpous fruits, first bpiral and then whorled, 

 of the Eanales, of which the Laurales are probably reduced 

 types, lead through the fruits of the water-lilies {Nyi)iph(£a) 

 and of Sarracenia to that of the poppy {Fapaver)] and in the 

 same tribe we have reversion to apocarpy in Platystemon and 

 a transition to the siliqua in Glaucium and Chelidonium. 

 Among Cruciferm the genus Tetraiwma (an illustration of the 

 fact, well known to biologists, that exceptional forms teach us 

 more than those which are regular or typical) indicates the 

 close affinity to the other Parietales, the capsules oi Resedacece, 

 ViolacecB, &c. ; and we have here probably a great " centre of 

 divergence" leading to the Discijiorm, Guttifercdes, Malvales, 

 and CentrospermcB. Of the latter mention has been made 

 already ; among the Malvales I can only now refer to the 

 succulent Malvaviscus and the sand-box tree {Hura crepitans) 

 which indicates that relationship between the Malvaceae and 

 Eiq^horhiacecB which is paralleled by that between Tiliaceie 

 and UrticacecB ; among the Guttiferales the cax^sule with 

 central placentation leads from Camelliacea to Ericacece ; and 

 among Discijiorce the superior schizocarp with a central 

 gynophore in Geranium leads to the fruit of Tropaolum and 

 the stipitate capsule in the PattacecB, which, being sometimes 

 fleshy, passes to the "hesperidia" of the orange tribe, whilst 

 the Celastrales, with the varying "nuculanes" of the holly, 

 Euonymus, Buckthorn, and Vine, lead to the still more 

 variable fruits of the Sapindales, which range from the horse- 

 chestnut and Litchi to the winged "samara" of maple and 

 sycamore. 



The PerigyncB, commencing with the numerous related 

 fruit-types of Bosacece, among which the "et^erio" of achenes 

 in Potentilla perhaps represents the primitive type, lead 

 through the Drupacece to the legume, perhaps through Poviece 

 to the nut of the Cnpulifera, and through Sjnraa to the 

 Saxifrages. Here we get a semi-inferior fruit with the 

 carpels reduced in number, near which the branch-phylum of 

 the Bicarpellatce (well represented by the Umbellales) may 

 have been given off ; whilst it has certainly been a centre of 

 divergence leading through Hillebrandia to the Beyoniacea 



