202 GENERAL BOTANY 



large red petal which stands on the upper or poste- 

 rior side, and in bud wraps round the others. Under 

 and in front of it, are two much 

 smaller petals, and these in their 

 turn enclose two others which are 

 on the forward or anterior and 

 lower side (since the flower faces 

 horizontally). The arrangement 

 of the petals as seen from above 



DIAGRAM OF PETALS 



OF ERYTHRINA when the bud is cut across is 



something like this (fig. 48). 



In the centre of the flower is the narrow oblong 

 ovary, a thin hollow box in which is a row of ovules,, 

 and which extends upwards in a long thin style. 

 Round the ovary is a tube split open on the upper 

 or posterior side and divided at the end into nine 

 filaments each with an anther. In the open space 

 so formed lies a stamen with its anther. 



We may consider the flower as having ten stamens,, 

 of which nine are joined together into a tube which 

 is not complete because the tenth stamen is free. 

 When this arrangement occurs the stamens are said 

 to be diadelphous. When all the rest of the flower has 

 fallen off, the ovary lengthens into a long cylindrical 

 fruit, slightly constricted between the seeds. 



3. Now examine in the same way the flowers 

 of CROTALARIA JUNCEA the Sunn-hemp, PHASEOLUS 

 the Bean, DOLICHOS the Lablab, PISUM the Pea, 

 LATHYRUS the Sweet-pea or any other of that kind. 



Each flower is enclosed at first by five green 

 sepals, arranged as in C^ESALPINIA, one on the lower,, 

 anterior side, and two other pairs. 



