LESSONS IN LOTANY. 



without giving ourselves the trouble to appeal to all the charac- 

 i mentioned. Nevertheless, botanists who penetrate more 

 deeply into the study of plantd find it necessary to examine all 

 the characters present. 



Many species of Passion-flower are now common enough in 

 our gardens. For the purpose of examination we shall select 

 an individual 

 of the species 



t.TIIH'il 



, the repre- 

 sentation of 

 which we sub- 

 join i Fig. 152). 

 The student 

 will first ob- 

 serve, on glanc- 

 ing at the 



. 1 charac- 

 ics of the 

 specimen, that 

 the flower is 

 supplied with 

 three large 

 bracts, which 

 constitute 

 what botanists 

 term an tnvo- 

 lucrum. Pro- 

 ceeding in- 

 ward, we next 

 arrive at 

 what ? The 

 calyx? It 

 should be the 

 calyx, judging 

 from its posi- 

 tion, but the 

 appearance of 

 its separate 

 parts (sepals) 

 is different 

 from the ap- 

 pearance of 

 those sepals 

 we have al- 

 ready met 

 with. They 

 are not green, 

 but coloured 

 like the petals 

 of most flowers. 

 We have al- 

 ready stated, 

 however, that 

 amongst the 

 other trans- 

 formations of 

 parts which oc- 

 casionally en- 

 sue, the trans- 

 formation of 

 the calyx into 

 the appearance 

 of a corolla is 

 not unfre- ,, 

 anont So fre- SCUBTT GRASS (COCHLEABIA OFFICINALIS). 



quently, in- 

 deed, docs this 



occur, that mere green colour is not to be regarded as more 

 than a collateral circumstance. The external floral whorl is 

 klways considered by botanists as a calyx, whatever its colour 

 may be. That colour is often very brilliant, as in the fuchsia, 

 for example, where the gay-looking part of the flower is not 

 corolla or aggregation of petals, but calyx, or aggregation of 

 sepals. This assumption by the parts of the calyx of the 

 appearances usually presented by the corolla gives rise to what 

 botanists term a petaloid calyx. The term petaloid means 

 resembling a petal ; the termination otJ being derived from the 



1.10 



Greek word <8ot (ei-dos), likeneu, which word, in composition, 

 changes eid into oid. Directing the eye to the lower part of 

 the sepals, they will be observed to rise from a shallow cup-like 

 body, to which also are attached the petals and other portions 

 of the flower. As regards the petals themselves, they are 

 coloured similarly to the inside of the sepals, and are of the 



same colour on 

 both sides, by 

 which circum- 

 stance they 

 may be distin- 

 guished from 

 the sepals, M 

 also by the cir- 

 cumstance of 

 their not hav- 

 ing a little 

 horn, which 

 may be found 

 on examination 

 springing from 

 each of the se- 

 pals. 



We next ar- 

 rive at the fila- 

 mentary rays 

 which the 

 imaginative 

 Span i a r ds 

 compared to 

 the crown of 

 thorns ! What 

 are those rays? 

 They are petals 

 so modified i 

 shape that 

 they almost 

 present the 

 appearance of 

 stamens. This 

 modification, 

 and yet more 

 frequently ita 

 converse, sta- 

 mens modified 

 into petals, is 

 not at all nn- 

 freqnent in 

 many flowers, 

 as the result 

 of cultivation. 

 In the Passion- 

 flower tribe, 

 however, it 

 exists as the 

 usual condi- 

 tion of the 

 flower. Let us 

 now proceed to 

 examine the re- 

 productive, or 

 fruit and seed- 

 producing por- 

 tions of the 

 flower, which 

 are very pe- 

 Wo 



149. THE WALL-FLOWKB. 150. TRANSVERSE SECTION OF OVART 

 151. COLUMN OF PASSION-FLOWER. 152. SCARLET PASSION-FLOWER (PASSIFLORA AKABILIS). 



have already 



mentioned a cup-like body in connection with the struc- 

 ture of a Passion- flower. It corresponds with the part 

 lettered c in Fig. 151. From the centre of this cup s> 

 column-like body is observed rising aloft in the centre of 

 the flower, to which certain appendages are attached. The 

 nature of these appendages will at once be obvious. Exter- 

 nally, we easily recognise five anthers, and internally we 

 recognise the club-headed styles ; but looking again at 

 the stamens, we search in vain for the filament?, which are, 

 in foot, united to the stalk which elevates the ovary, 



