292 FREAKS OF PLANT LIFE. 



various animals are utilised as a means of transport. 

 In these, and various collateral ways, we are enabled 

 to associate the modifications of form with the mode 

 of distribution, and it is to a few of the most striking 

 examples of these different modes that this chapter 

 is devoted. Illustrations will also be found scattered 

 through other portions of this volume incidentally, 

 when given in association with other subjects, and 

 especially in the chapter on " mimicry," in which the 

 same type of structure, and, presumably, the same 

 mode of dispersion will be found repeated in different 

 and widely separated orders. Neither here nor there 

 have we assumed the exhaustion of so fertile a theme.. 

 When writing of hygroscopism we have already 

 alluded to the facility with which the seeds are dis- 

 persed from such fruits as burst open with violence 

 and jerk out their contents, as in the sand-box tree. 

 In a similar manner we might have instanced 

 Byttneria aspera, one of the order Sterculiacea, but a 

 more important tree in many respects is the 

 Mahogany tree (Swietenia mahogani), the woody 

 fruits of which separate so freely, and disperse the 

 seeds, that it is difficult to meet with any but frag- 

 ments of the capsule in the countries where it 

 flourishes. Another advantage is possessed by this 

 tree, in that the seeds themselves are winged, like 

 a samara, so that two modes of dispersion are 

 combined in the same fruit. 



