82 THE COMMENCEMENT OF THE PHANEROGAMIC FRUIT. 



reference to fig. 208 ''. Here no ovarian cavity is formed, the carpels are distinct 

 from one another, and are spirally inserted upon the termination of the caudex; they 

 are deeply lobed, certain of the segments being transformed into ovules. 



Thus, while the ovules of Orchids seem to be equivalent to hairs, those of Cycads 

 represent leaf-segments. In both cases the relations of the parts seem obvious. 

 But in a great many cases the significance of the ovules is by no means so obvious, 

 especially when the developmental history admits of various interpretations. In 

 such doubtful cases antholysis offers a welcome assistance — that is, where this 

 " loosening" and " greening" involves not only the ovary but also the ovules. 



Especially valuable in this respect are certain cases of antholysis of the flowers 

 of the Sundew (Brosera). Whilst in the normal flowers of this plant the ovules 

 arise on the inner surface of the united carpels, in the foliaceous or antholytic ones 

 they are borne upon the open and isolated carpels as glandular tentacles, like those 

 usually occurring upon the leaves of this plant (cf. fig. 212^). On many of the 

 carpels these glandular structures are fused together in little clusters (212'), and 

 these fused structures show various transitional stages leading up to inverted 

 ovules (figs. 212 ^' ^' i"' '^''■- ^^). From a study of these cases one may infer that the 

 integument of the ovule here is equivalent to a group of tentacles. 



Very diff"erent is the case of the Larkspur (Delphinium). In normal flowers the 

 ovules arise from the infolded margins of the carpels, each of which forms an ovary 

 {cf. fig. 210 *). But in the foliaceous flower the carpels are open and their margins 

 lobed (cf. fig. 210 « and fig. 212 '^). They recall the carpels of Cycas (fig. 208 ^ and 

 agree with it in that some of the segments are converted into ovules. And it must 

 be especially noted that the leaf -segments are so folded that a pit-like excavation is 

 formed (cf. figs. 212 ^* and 212 ^°). Thus it appears that in the Larkspur the ovular 

 integument is formed by the folding of the leaflet-like segments. Difierent again is 

 the case of the Clover (Trifoliwm), of which an antholysis is shown in fig. 212^* 

 The ellipsoidal ovules, which are borne along the fused margins of the infolded 

 carpel in the normal flower, are here replaced by little, leafy structures resembling 

 leaflets on the margin of the open carpel (cf. figs. 212 ^^ and 212 ^'). These leafy 

 structures are neither rolled up nor folded, and from each projects the nucellus of 

 an ovule, or rather a mass of tissue corresponding to a nucellus, surrounded by an 

 enveloping wall (cf. figs. 212 1^- 1^- ^c 21 ). This wall may be regarded as representing 

 the inner integument of the ovule, whilst the outer one is replaced by a leaflet. The 

 monstrous ovules in the ovary of the Common Sallow (Salix Oaprea, fig. 212^') 

 show similar relations, except that the green, leafy structure upon which the 

 nucellus of the ovule is inserted is folded along its midrib and has a fimbriated 

 margin (fig. 212 5"). Of especial interest are the monstrous flowers of Rumex 

 scutatus (cf. fig. 212 2*' 2^' 28' 27, 28)^ a plant common on the debris slopes of limestone 

 mountains. In the normal flower of this plant the ovary is egg-shaped, and consists 

 of three carpels united edge to edge (figs. 212 ^^ and 212 ^^). But in these monstrous 

 cases it is enlarged from six to tenfold, and modified into a funnel-shaped tube open 

 above (212 2^.25, 26,27) j^j-q^^ ^j^^g ^j^g ovule, also modified into a tube, sometimes 



