MIMICRY. 337 



stance invests the seeds in some of the A sclepiadacece, 

 which family is far removed from the above, and also 

 from the Convolvulacece, in which latter family there 

 are instances of Ipomcea, the seeds of which are 

 invested in one species with a substance like "silk- 

 cotton," and in another with a substance resembling 

 a native Indian cotton, approaching to the texture 

 of wool. 



It would not be difficult to go on repeating 

 instances of such coincidences in fruits and seeds for 

 many pages, but we, must rest content with another 

 series. Most persons are aware that the prevalent 

 type of seed in the fir tree, or coniferous family, 

 consists in a brown hard seed, with an extension of 

 membrane into a kind of wing. Of course, there are 

 different forms of pine seeds, some of which have no 

 wing ; but we desire to indicate that the winged 

 type is repeated in other families, not at all related 

 to the Conifera. This is the case with the seeds of 

 some of the species of Lagerstrtxmia, which are allied 

 to our " purple loosestrife ; " also in Cedrela, and some 

 other genera in the natural order to which the 

 mahogany tree belongs ; and, to some extent, in 

 Ailanthus, wherein there is an approach to the 

 samara of the ash, the winged fruits being, in fact, 

 " samara," and not seeds. Fir cones themselves are 

 almost imitated in the fruits of some of the palms, 

 in so far as appearance goes, although in structure 



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