31 



Lychnis; nocturnal as in Saponaria ofiScinalis and Nic()tiana 

 afBnis, etc. 



Carrion Flowers. Dull in color, yellow, brown, dis- 

 agreeable urinary or carrion-like odor. Stapelia, Crataegus, 

 Smilax herbacea. 



Deceptive Flowers. Insects (flies) attracted by false 

 nectaries. (Parnassia). 



After having briefly considered the 

 structure of insects it is now in order 

 to take up the attractive features of flowers. I think no one 

 can doubt that bright colors assist greatly in attracting in- 

 sects. Not all insect pollinated flowers are of bright color. 

 Many flowers that are pollinated at night are white, as in - 



Attraction of Insects. 



Fi^. 17. Nectaries. I. Buttercup (RanuTiculua acris) \ II. longitudinal section ; 

 III. Yellow Battle ( Khinanthus) ; IV. Umbellifer (Anthriscus sylvestris) ; V. 

 Monk's hood (Aconitum 9iapellu8) ; lit. three times enlarged; II. eight times 

 enlarged; IV, six times enlarged; V. natural size. n. nectary; b. petal; t. 

 nectar; f, Ic, ovary. (After Behrens.) 



Datura and Nicotiana. Some night pollinated flowers are 

 pink and other colors, as in Phlox paniculata. 



Grant Allen says: "We can hardly resist the inference 

 that the colored whorls represent an intensification of the 

 natural tint in growing shoots and floral organs, slowly modi- 

 fied by the selective action of the insect eye." "Mueller, who 

 has carefully noted flowers and their insect visitors, observed 



