SUPPRESSION OE ABORTION OK PARTS. 265 



rendered the latter abortive also, leaving those of the third row alone 

 to fulfil their proper ofiice. And in a South African genus, Monso- 

 nia, five stamens actually occur in the place of these glands, making 

 fifteen real stamens, or three circles. The general plan of the flower 

 is the same in the Flax family, except that the glands which answer 

 to the outer rank of stamens are still 

 less conspicuous, and those of the next 

 circle are reduced to small abortive 

 filaments, or to minute teeth in the 

 ring formed by the union of aU the 

 filaments into a cup at the base, leav- 

 ing five perfect stamens, which, though 



they alternate with the petals indeed, belong to a third circle (Fig. 

 422, 423). In a few species of Flax, this second circle of stamens 

 is perfectly obliterated, so that no vestige is to be seen. 



487. The complete suppression of two or three of the circles be- 

 longing to the complete flower, and of a part of the members of what 

 remains, reduces a blossom to the last degree of simplicity. Among 

 the simplest of perfect flowers are those of Callitriche (Fig. 1136 - 

 1138), which have neither calyx nor corolla ;. and only one stamen, 

 as is expressed in the annexed diagram (Fig. 424) ; yet the four- 



lobed pistil shows 



that the blossom was 

 

 ^Y^- f\ constructed on the 



>Caj o?0 o U o plan of four. And 



' 7~- T ' ?S T" even this stamen is 



j24 a i:i3 b a 4-JS b 



suppressed in cer- 

 tain blossoms, and the pistil in others. In Euphorbia (also to be 

 illustrated under the family to which it belongs. Fig. 1143) the 

 flowers are always separated, and the staminate blossom is reduced to 

 a single stamen, the pistillate to a single three-lobed pistil (Fig. 425). 

 And in the Willow, as already noticed (438), the pair of stamens 

 which represents one sort of blossom, and the single pistil which repre- 

 sents the other, are widely separated, being borne on distinct trees. 



FIG. 422. Flower of Linum perenne, 423. Its stamens and pistils enlarged. 



FIG. 424. Diagram of a perfect flower of Callitriche, with no floral envelopes, one stamen, 

 and a four-celled pistil. 



FIG. 425. Diagram of the monoecious flowers of Euphorbia : a, the pistillate flower re- 

 duced to a mere three-celled pistil ; and 6, one of the staminate flowers reduced to a single 

 stamen. 



FIG. 426. Diagram of the dioecious flowers of the Willow : a, one of the pistillate flowers 

 reduced to a solitary pistil J 6, a staminate flower reduced to a pair of stamens. 



23 



