336 NATURE STUDIES. 



comparison with it, we shall be able to see exactly 

 wherein the two flowers differ, as well as why the one 

 has gained an advantage in the struggle for existence 

 over the other. 



The outside whorl of the buttercup consists, of 

 course, of five separate greenish sepals, which together 

 make up its calyx. Inside the sepals come the five 

 golden petals composing the cup-shaped corolla ; and 

 inside the petals, again, come the numerous stamens,, 

 and the equally numerous carpels, or unripe fruits, 

 each containing a single, solitary little seed. More- 

 over, all these parts are regularly and symmetrically 

 arranged round a common centre, so as to form a 

 series of concentric whorls. But when we look at 

 the monkshood, we see no such simple and orderly 

 arrangement in its architectural plan. At first sight, 

 we recognise no distinct sepals or petals; and the 

 coloured organs that take their place are very irregular 

 in shape, and disposed in an unsymmetrical fashion 

 or rather, to speak more correctly, their symmetry 

 is not radial, but bilateral. When we begin to pull 

 our blue blossom to pieces, however, we gradually 

 recognise the various parts of which it is composed. 

 First of all come five sepals, not greenish, as in the 

 buttercup, but bright blue; and not all alike, but 

 specially modified to fulfil their separate functions. 

 The uppermost sepal of all is helmet-shaped, and it 

 forms the curious cowl which gained the plant its 

 .suggestive name from our mediaeval ancestors. The 

 two side sepals, to right and left, are flatter and 



