ANATOMY AND PHYSIOLOGY OF PLANTS. 241 



seed vessels, it is only necessary to refer to what has been 

 given on them in the Elements of Botany. Whatever 

 may be their character, they are formed from the germen 

 or ovary, and consist of the solid components of that 

 part, in a peculiar state of transformation. 



The changes of the ovary to a seed vessel is a very gradual pro- 

 cess. After the embryo seeds have been acted upon by the pollen, 

 the calyx, corolla, stamens, and even style of the pistil, commonly 

 fade and fall ; the ovary alone remains, and undergoes very differ- 

 ent changes of form, structure and properties in different plants, 

 until it becomes the fruit or seed vessel. Thus the pear, the apple, 

 the peach, and so on, during the blooming of the flower, were 

 nothing more than the small germen of the pistil. 



19. The valves of the capsule, but particularly the 

 partitions by which it is divided into cells, are composed 

 of a thin and skinny membrane, or of an epidermis 

 covering a pulp more or less indurated, and interspersed 

 with longitudinal fibres. 



The usual parts into which capsules are divided, has been men- 

 tioned under the Language of Botany. 



20. The pods and legumes are composed of an epi- 

 dermis enclosing a firm but fleshy pulp, lined for the 

 most part with a skinny membrane ; and of bundles of 

 longitudinal fibres, forming the seam. 



21, The drupe consists of an epidermis enclosing a 

 fleshy pulp, which is sometimes so interwoven with a 

 multiplicity of longitudinal fibres as to seem to be 

 formed wholly of threads. 



