86 MORPHOLOGY, OE COMPARATIVE ANATOMY. 



lops into a shoot which assumes a vertical direction, thus occupying the 

 position of the inflorescence. Such branches are called by French botanists 

 usurping branches. In a few cases absolute partition of the growing point 

 has been observed one division forming a tendril or an inflorescence, the 

 other forming a new vegetative axis, as in Vitis vulpina observed by 

 Warming. 



Duration. The inflorescence, like the leaf, varies in its duration. 

 The staminal catkins of the Amentaceae, such as the Oak, Hazel, 

 Poplar, &c., fall off as soon as the pollen is discharged from the 

 stamens, and they are called caducous. In many cases the inflo- 

 rescence, or the individual peduncles, separate by a disarticulation 

 when the fruit is ripe, as in the Apple, Cherry, &c. ; the term de- 

 ciduous is then applied. In the Rose we observe the dried-up fruit 

 long remaining, like the cones of Firs, &c., after the seeds have 

 become matured ; these are persistent. Sometimes the peduncles 

 undergo expansion during the ripening of the seeds, so as to form 

 part of the fruit ; such an inflorescence or peduncle is called ex- 

 crescent. The Fig, the Pine-apple, and other fruits are formed of 

 excrescent inflorescences; the Cashew-nut (Anacardium) has an 

 excrescent peduncle. 



Characters afforded by the Inflorescence. For descriptive pur- 

 poses the inflorescence must be treated as the ramifications of 

 the stem, noting also the number of the flowers, their mode of 

 expansion, and other peculiarities as explained in the foregoing 

 sections. 



Sect. 7. THE FLOWEE. 



The Flower, the characteristic reproductive apparatus of the 

 higher plants, consists of no new elements superadded to the fun- 

 damental organs of the vegetative regions, but is merely an assem- 

 blage of these organs modified in certain essential particulars so as 

 to fit them for exercising new functions. A flower is a modified 

 shoot, in which the internodes of the stem are seldom developed ; 

 while the leaves, arranged according to the general phyllotactic 

 laws, are more or less different in form and texture, and have part of 

 their tissues developed into more highly specialized products, dis- 

 tinguished both in anatomical and physiological characters from 

 those associated with vegetative leaves. 



The theory of the construction of the flower rests upon proofs derived 

 from various sources, such as teratology, or the study of exceptional 

 growths. The strongest confirmation of the views arising out of the ob- 

 servation of such cases is obtained by comparative morphology, by the in- 

 ternal structure, and by the investigation of progressive development, or u or- 

 ganoyeny" which latter supplies a clue to the original ancestral form. 



