372 



NA TURE 



[August 17, 1882 



immediately pointed out. Perhaps its very inconspicuous- 

 ness saves it from the obtrusive visits of undesirable 

 insect guests. The flowers of Hedera helix, common ivy, 

 are also yellowish green. In the allied family of Umbelli- 

 ferie many flowers have declined to similar greenish 

 tints ; but this can hardly be their primitive colour, as 

 they have an inferior ovary, which marks high develop- 



Fig 27. Fie. 28. 



Fig. 27. — Single floret of Polerhtm sanguiso'ba. green and anemophil -us. 

 Fig. 28. — Single fi\>ret of Sangnisorba officinalis, purple and entomo- 

 philous. 



ment. Smyrnium olusatrum in this family, and Chrysos- 

 plenium among the Saxifraqaceoe, exhibit very well the 

 steps by which green corollas or perianths may be pro- 

 duced from originally white or yellow flowers. Their 

 high structural development obviously negatives the 

 notion that they are primitive green flowers ; and we 



-Single blossom <fS mh European Fraxmuso* 



with calyx and f mr-lobed white corolif 



flowering ash, 



must necessarily conclude that they have become green 

 for some special functional purpose of their own. 



The orchids themselve=, that most specialised of ento- 

 mophilous types, show us other examples of flowers which 

 have become more or less green ; such as Malaxis palu- 

 dosa, which has a yellowish tinge; Liparis loti ilsc 



Fig. 30.— Thr 



; of naked flowers of British ash, Fra 



without calyx or corolla. 



yellowish; Epipaclis latifolia, greenish brown; Listera 

 ovata, grass-green; Habenaria viridis, yellowish green ; 

 and Her minium monorckis, pale greenish yellow. Why 

 these highly-developed entomophilous blossoms should 

 have found green suit them better than white, pink, or 

 purple, it would be hard to say ; but the fact remains in- 

 disputable; and it would be almost inconceivable that 



flowers of so high a type should have remained green all 

 through the various stages of their long previous develop- 

 ment. We may confidently set them down as products 

 of incipient degeneration. 



Among polypetalous flowers we get some equally inter- 

 esting facts. Helleborus viridis, a doubtfully English 

 ranunculaceous plant, has small green petals, employed 

 as nectaries, and concealed by the large green sepals. 

 It is entomophilous, and much visited by insects. Instead 

 of being one of the least-developed Ranunculacece, how- 

 ever, it is one of the most advanced and highly differen- 

 tiated types. In the lily family, again, the onion genus 



of d ig's mercury, green. Fig. 32.- 

 - of dog's mercury, green. 



{A Minn) is a small, and often degraded, group, whose 

 more retrograde members produce green in place of 

 purple or white flowers. In Allium vineale, and some 

 others, the flowers often degenerate so far as to become 

 small caducous bulbs. Here, degeneration is the only 

 possible solution of the problem presented by the facts. 



More frequently, however, reversion to wind-f rtilisa- 

 tion (probably the primitive habit of all flowering plants) 

 has produced green blossoms among angiosperms, This 

 may result in two or three distinct ways. Either the 

 corolla may become dwarfed and inconspicuous, or it 

 may coalesce with the sepals or calyx-tube, or it may 



1.33. — Oust female flow* 



s reduced I 

 where the filament j >ins the peduncle, 

 green, the stam ns opposite the sepals 



s of spurge, green, in a common 

 . a sing e 5 



Fig. 34.— Male flower of nettle. 



cease to be produced altogether. We may take the 

 plaintains {Plantago) as a good example of the first- 

 named case. Here we have tubular florets with four 

 corolla-lobes, apparently descended from some form not 

 unlike Veronica (though with four cells to the ovary) but 

 immensely degraded. The corolla is thin and scarious, 

 and its lobes are tucked away at the sides, so as not to 

 interfere with the stamens and style. The^e, 

 in most wind-fertilised plants, hang out freely to the 

 breeze; so that the whole spike when flowering shows no 

 signs of a corolla from without, but seems to consist 

 entirely of scales, stamens, and styles, just like a sedge or 



