CHAP. VI. FUNCTION OF REPRODUCTION. 277 



nical geographer ; and a complete description of the 

 various appendages by which their dispersion is assisted 

 would form an interesting topic of inquiry. We may 

 just refer to three forms of fruits which are more espe- 

 cially connected with the physiology of our subject, and 

 which exercise a marked influence on the dissemination 

 of the seed. 



(276.) In pseudospermic Fruits. In this class we 

 may include all fruits whose pericarp is so closely 

 attached to the seed, that it cannot readily be distin- 

 guished from one of its integuments. These are often 

 erroneously considered as naked seeds, and not as com- 

 plete fruits. To this class belong the various kinds of 

 corn ; the seeds of the umbelliferse, as carrots, parsnips, 

 &c. ; and of the composite and others. In these cases, 

 the seed is sown together with the seed cover (or peri- 

 carp), and the young plant has this additional obstacle to 

 overcome before it can grow. Many fruits of this kind 

 are furnished with wing-like appendages, as in the ash 

 and sycamore ; or with down, as in the valerian, but 

 more especially in some of the compositae, as the dande- 

 lion, thistles, and others. All these contrivances are 

 manifestly intended to assist in the dissemination of the 

 seed ; but in many cases the pseudospermic seeds have 

 no such provision, and are even so arranged on the 

 plant as to secure it against any very extended dis- 

 persion. 



(277-) In fleshy Fruits. The soft pulp which sur- 

 rounds the seeds of fleshy fruits does not appear to ac- 

 celerate their growth when sown with them ; and by 

 its tendency to rot, it prevents them from keeping so 

 long as when they are divested of it. As a sort of 

 compensation for the injuries which they might receive 

 on this account, many seeds of pulpy fruits are encased 

 in a hard stone or bony envelope which resists the action 

 of moisture, and protects them from the influence of 

 the rotting pulpy mass on the exterior. All fruits of 

 this kind fall to the ground close to the plant which 

 bears them, and must depend upon accident for their 

 T 3 



