THE PLAX OF THE FLOWER. 



8T 



spur the V flowers have but four petals, and in monk's-hood, also v/> the petals are 

 apparently but two strangely deformed bodies. A careful inspection, however, 

 generally reveals the other three, very minute, in their proper places, as displayed 

 in the cut. (283.) 



427. " ORGANS OPPOSITE" is a condition much less frequent than " organs alter- 

 nate," but is highly interesting, as being sometimes characteristic of whole families. 

 Thus in the primrose, thrift, and buckthorn families, the stamens always stand op- 

 posite to the petals ! 



428. How HAPPENS THIS ? Among the primworts this question is solved in tho 

 flowers of Lysimachia and Samolus, where wo find a circle of five teeth (abortive 

 filaments) between the petals and stamens, alternating with both sets, thus restoring 

 the lost symmetry. Hence we infer that in such cases generally a circle of alter- 

 nating organs has been either partially or wholly suppressed. In tho buckthorn, 

 however, a different explanation has been given. 



Diagrams. 272, Flower of Samolus, showing the rudimentary stamens alternating with the 

 perfect. 273, Flower of a Labiate plant, showing the place of the deficient stamen. 274, Flower 

 of Asarum ; three sepals, twelve stamens, etc. 275, Flower of Saxifrage ; two pistils, ten sta- 

 mens, etc. 



429. THE MULTIPLICATION OF ORGANS is exceedingly common, and usually ac- 

 cording to a definite plan. The increase takes place, as a rule, by circles, and con- 

 sequently by multiples. That is, e. g. t the stamens of a V flower, if increased, will 

 be so by 3s ; of a V flower by 5s, etc., sometimes to the extent of twenty such 

 circles. 



430. CROWFOOTS AND ROSEWORTS. In tho crowfoot family the stamens aro al- 

 most always multiplied. The carpels are also generally multiplied, yet often, on the 

 contrary, diminished, as in the pseony. In Rosaceas, also, the stamens are generally 

 multiplied, while the carpels exist in all conditions as to number. Thus in straw- 

 berry they are multiplied, in the apple they are regularly five, in agrimony reduced 

 to two, and in tho cherry to one. 



431. OTHER CASES. In Magnolia the V flowers have three sepals in one circle, 

 six or nine petals in two or three circles, numerous stamens and carpels in many 

 circles of each. In tho V flowers or blood-root there are two sepals, eight petals, 

 twenty-four stamens, and two carpels. 



432. INCREMENT BY CLUSTERS (CHORISIS). In other cases the organs seem to be 

 increased in number by clusters rather than by circles, as when in the same circle 

 several stamens stand in tho place of one, e. g., in squirrel-corn, st. johnswort, lin- 

 den. Such cases afford wide scope for conjecture. Perhaps each cluster originates 

 by division, as the compound from the simple leaf; or as a tuft of axillary leaves : 

 or thirdly, by a partial union of organs. 



433. APPENDICULAR ORGANS ( 407) consist of spurs, scales, crown, 

 glands, etc., and often afford excellent distinctive marks. The old term 



