THE FLOWEB. 87 



We may, in the first place, remark upon what is taught by the study 

 of development. Flowers are common in which the organs stand in 

 regular circles, and in which the organs of each circle agree in colour, 

 size, and so on; but in many cases we find deviation from this regularity: 

 the arrangement of the organs becomes changed, and the parts of parti- 

 cular circles become more or less different among themselves as, for ex- 

 ample, in the flowers of the Pea-tribe, of Labiatse, &c. But when we 

 examine the buds of these flowers in a very young state, we often, but 

 not always, find the rudimentary organs regularly arranged, and, while in 

 the state of cellular papillaB, agreeing exactly in all external characters. 

 The subsequent irregularity is a result of special growth, for a special 

 purpose, at a later epoch. In didynamous stamens, for example, the 

 longer pair do not exceed the others until a late period of their develop- 

 ment. 



Transitional Forms. The original uniformity and homogeneity of 

 the organs of flowers are not always so completely lost in the maturation 

 of the structures, that the different secondary types of organs, sepals, 

 petals, &c. become entirely distinct. The study of comparative morpho- 

 logy reveals many cases of transition from one kind of organ to another, 

 illustrating, in a very interesting manner, the doctrines of morphology. 



In Calycanthusjloridus and the Camellia the numerous pieces of the 

 floral envelopes present a spiral arrangement, and it is impossible to find 

 a distinct line of demarcation between the bracts, the calyx, and the 

 corolla. In species of Cornus and Euphorbia, the coloured bracts of the 

 involucre assume quite the aspect of a coloured calyx or corolla. In the 

 White Water-lily (Nympheea), a transition between sepals and petals is 

 seen in the segments of the calyx, which are green outside and petaloid 

 internally, while we have perfectly petaloid sepals in many flowers, as in 

 Aconites, Larkspurs, &c., and particularly in the showy bulbous Mono- 

 cotyledons commonly cultivated, e. g. the Lily (Lilium), Tulip, Crocus, 

 &c. 



In the Water-lily (Nymphaa) we observe a gradual transition between 

 petals and stamens, the latter appearing first as petaLoid plates, with anther- 

 structure on the edges. In Canna it is the ordinary rule for the stamen 

 to be a kind of petal bearing an anther-lobe on one upper edge. A more 

 or less expanded petaloid state of the filament is not unusual, and in the 

 Mistletoe the stamens are flat, leafy organs, with the pollen developed in 

 the parenchyma of the inner face. 



The stamens and pistils being so diametrically opposed in their physio- 

 logical characters, we naturally do not expect to find any transition 

 between these organs in normal flowers, though in monstrous develop- 

 ments such transitions are frequent. 



Teratology. The study of Teratology, the interpretation of exceptional 

 growths by reference to laws of development more or less interfered with 

 by external agency, is very instructive in regard to Morphology. In the 

 exceptional products of nature or, still more, of art, we find illustrations of 

 almost every possible kind of the general proposition above mentioned. 



Phyllody. Cases are not unfrequently observed where the entire 

 flower is replaced by a fascicle of green leaves, especially in the Alpine 

 Strawberry. In wet seasons it is not uncommon to find flowers of the 



