20 STRUCTURAL BOTANY. 



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 alternating organs has been either partially or wholly sup- 

 pressed. In the Buckthorn, however, a different explanation has 

 been given. 



74. Redundancy. The multiplication of organs is exceed- 

 ingly common, and usually according to a definite plan. The 

 increase takes place, as a rule, by circles, and consequently by 

 multiples. That is, e. g., the stamens of a V flower, if increased, 

 will be so by 3s ; of a v' flower by 5s, etc. sometimes to the ex- 

 tent of twenty such circles. 



75. In the Crowfoot family the Btamens are almost always multiplied. The carpels are 

 also generally multiplied, yet often, on the contrary, diminished, as in the Pieony. In 

 Rosaceae. also, the stamens are generally multiplied, while the carpels exist in all condi- 

 tions as to number. Thus in Strawberry they are multiplied, in the Apple they are regu- 

 larly five, in Agrimony reduced to two, and in the Cherry to one. In Magnolia the %/ 

 flowers have three sepals in one circle, six or nine petals in two or three circles, numer- 

 ous stamens and carpels in many circles of each. In the / flowers or Blood-root there 

 are two sepals, eight petals, twenty-four stamens, and two carpels. 



76. 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 the place of 

 one e. g., in Squirrel-corn, St. Johnswort, Linden. Such cases afford wide scope for con- 

 jecture. 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. 



I'eriew. 64. How to study flowers. Five general modes of deviation from the Type. 

 65. The radical number. How expressed. Give examples. 66. Incomplete flowers. 

 Apctalous flowers. Naked flowers. Examples. 67. Imperfect flowers. The sterile. 

 The fertile. Monoecious. Dioecious. Examples. 68. Neutral flowers. 60. Unsymmet- 

 rical flowers. 70. Case of the Mustard. Case of the Mint tribe. 71. Case of the Poppy. 

 Larkspur. 72. Organs opposite. 73. How explained. 74. Law of the multiplication of 

 organs. Illustrate this in Pinks, Lilies, Syringa, Magnolia. 



CHAPTER IV. 



ANOMALOUS FLOWERS CONTINUED. 



77. Appendicular organs consist of spurs, scales, crown, 

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

 old term nectary was indiscriminately applied to all such organs, 

 because some of them produced honey. 



78. Spurs are singular processes of the flower, tubular and 

 projecting from behind it. In Columbine each petal is thu 



