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CHAPTER VII. 

 TRACES OF UNITY IN PLANTS AND ANIMALS. 



BETWEEN plant and animal and between animal and 

 plant there are many superficial traits of resemblance 

 some of which it may be well to call to mind before 

 proceeding to consider whether there are any deeper 

 ties of kindred beneath them. 



The flower of the dove plant (Peristeria data), the 

 loveliest of all orchidacean flowers, consists of a rose- 

 like crown of white sepals, from the bosom of which a 

 white dove, with outstretched wings, is, as it were, upon 

 the point of taking flight The flowers of many other 

 orchids resemble insects of various sorts in the very 

 strangest manner insects which have only to make a 

 slight effort to break loose from their fetters and get 

 away ; and not unfrequently the plants to which these 

 flowers belong, as if unwilling to be tied down like ordi- 

 nary plants, are parasites living on the topmost parts of 

 lofty trees, and resting rather than clinging there, for 

 more than half their roots dangle loosely in the air as 

 aerial roots. Several of the globular echinocacti, with 

 their long spines and quasi-ambulacral lines, set with 

 buds in place of pedicellaria, are startlingly like globular 

 sea-urchins. The Astrophytum myriastigma is not less 

 like a short-armed star-fish, the buds being still arranged 

 in lines after the manner of the feet in the radiate 



