SECT. I. ORGANOGRAPHY AND GLOSSOLOGY. 



119 



assume the form and structure of secretory glands, and 

 of various processes and appendages, of an anomalous 

 character. In many cases, the parts which have 

 degenerated from their usual condition, assume a 

 highly developed structure, and become more leaf- 

 like. Thus, we find double flowers are often formed 

 by the stamens having put on the appearance, and 

 all the characters of petals, organs which are usually 

 of larger dimensions, though of inferior importance 

 in the floral economy. In some plants, as the com- 

 mon white Water-lily (Nymphaea alba), the transition 

 from the character of a petal to that of a stamen, is so 

 very gradual (fig. 132.), through successive whorls of 



these organs, that it is hardly possible to determine where 

 one set begins and the other terminates. 



(117-) Causes of Abortion and Degeneration. An 

 inquiry into the causes of abortion and degeneration, 

 more properly belongs to our physiological department, 

 but may as well be alluded to in this place. The par- 

 tial or total abortion of certain organs, is very frequently 

 occasioned by accidental circumstances from some 

 impediment thrown in their way, from a deficiency of 

 light in a particular direction, and many other external 

 causes. In these cases, when the influence is removed, 

 the suppressed organ will sometimes appear, and assume 

 its proper character. Thus, in trees, it seldom happens 

 that all the buds generated in the axills of the leaves, 

 are developed into branches ; but many of them remain 

 dormant, especially about the lower parts of the stem ; 

 and it is not until a better supply of light and air is 

 i 4 



