ORCHIDS. 



237 



LXII. OTHER ORCHIDS.* 



Fig. LXII.— a flower of Or- 

 chis Psychodes : o, the twist- 

 ed ovary ; s, the spur. 



Description. — Among the flowers of June, the practiced 

 collector, acquainted with 0. spectdbilis, will recognize yet 

 other kinds of Orchis, or of its cousins. In old woods 

 abounding in Hemlock 

 and Pine, let him expect 

 the Great Round-leaved 

 Orchis (0. orbiculata). 

 It will be known by its 2 

 large (5 '-8'), rounded, 

 polished, parallel-veined 

 leaves lying flat on the 

 ground, and its tall (2 

 ft.), bracted scape bearing a raceme of stra< 

 gling greenish-white flowers. 



Analysis. — The student will mark the 

 form of the column, so different from that of 

 0. spectaiiUs. Here the sticky glands are 

 naked, disk-form, and widely aj)art, as are also 

 the pollinia which they support. jS'ote also the long strap- 

 shaped lip, the roundish upper sepal, and the slender spur 

 nearly 2' long. No insects but the largest Sphynx Moths 



* In the Orchids are seen the highest evidence of the mutual relations of flowers 

 and insects. In numerous species special adaptations are carried so far that while 

 self-fertilization is iinpossiblc,«hc service of crossing is limited to a sin<rle species of 

 insect only. Thus Nature here emphasizes the principle (.f cross-fertilization ; and 

 experience has shown that plants raised from seeJ i)roduced by flowers fertilized by 

 pollen from another flower, are stronger, usually taller, bear more flowers and pro- 

 duce more seeds than those grown from the seed of i)lants fertilized by their own 

 pollen. "Nature seems everywhere to have forbidden the banns of intermarriage, 

 and her decree is carried out whenever possible, from mosses to men." Tliere have 

 been cases in the history of some tribes wliere intermarriage only could save the race 

 from extinction. Similarly, among i)lants, there are some flowers which have to 

 adopt self-fertilization as a rule, or as a last resort ; but the pre-eminent law is against 

 it even more in plants than in animals, enforced by the very structure of the flowers. 

 It is hardly too much to assert that every sjjecies of flowering i)lant has its peculiar 

 modification to realize this end. It is as if jjlants themselves were conscious of the 

 importance of this principle, and so adopt some device to carry it out. 



