CLAYTOtflA. 41 



The Inflorescence. The flowers form a cluster above 

 the leaves at the termination of the stem. In the cluster 

 appears (a to b) a general foot-stalk the peduncle support- 

 ing the whole; an axis (b to c), called the rachis (spine) 

 running through the midst ; and several special foot-stalks 

 (d), pedicels, branching from the rachis, each bearing one 

 flower. The whole cluster so arranged is a raceme. * The 

 flowers do not all open at once, but in a regular succession, 

 beginning with the lowest in the raceme and ending with 

 the highest. While the lower are in bloom or past bloom, 

 the upper are in bud or just opening. The word centripetal \ 

 is used to express this special mode of inflorescence. 



The Flower is made up of four sets of organs, each set 

 a circle one within another. First, the calyx or cup (c) con- 

 taining all the rest. It consists of 2 green leaflets called 

 sepals. Next within is the delicately colored corolla consist- 

 ing of 5 rose-tinted and red-lined petals \ (p). Third, a 

 circle of 5 stamens (s), each consisting of a slender filament 

 (/) tipped with an oblong anther (h). We must not fail to 

 observe their unusual situation each opposite to (opposing) 

 a petal (2). Observe also (3, 4) how the anther is attached 

 to the filament, how its 2 cells open, and how it seems to face 

 this way or that. Here it faces the pistil, and we say it is 

 introrse ; and the cells open lengthwise. And fourth, the 

 pistil (5) in the center of the flower, consists of one ovary, 

 one style and three stigmas (g). If we dissect the ovary (6), 



* Sometimes in vigorous specimens the rachis divides, forming two racemes or a 

 double raceme. 



t The top of the inflorescence is regarded as its center, the base the circumfer 

 ence ; hence the fitness of the word (centrum^ the center, peto, I seek). 



t The colored converging lines and veins which mark the petals of Spring Beauty, 

 Pansy, Geranium and other flowers, serve as honey-guides for insects. They inva- 

 riably converge towards the nectaries at the base of the petals and stamens. An 

 insect following them is led directly to where the honey is secreted. On its way its 

 body is dusted with pollen, or, already dusted, is brought into contact with a pistil 

 ready to receive it. 



