164 Trans. Acad. Sci. of St. Louis. 



pollen from the long anthers. When the keel is depressed, 

 the pollen is forced out in a band partly by the aid of the 

 style and the shorter anthers, which have not yet discharged. 

 It is quite probable that effectual pollination does not occur 

 until the stigma has been rubbed. 



The banner often extends horizontally and the keel in a 

 vertical position. The flowers are adapted to the smallest 

 bees and are abundantly visited for nectar by Calliopsis andre- 

 niformis Sm. §. Of nine species of Calliopsis occurring 

 here, this species has the longest flight — June 3 to September 

 18 — extending throughout the blooming season of Stylos- 

 anthes. 



According to Kuhn (1) Stylosanthes has cleistogamous 

 flowers, but it is not stated in which of the about fifteen 

 species close pollination occurs. Foerste (3), quoting Chap- 

 man (2), says of S. elalior: " It has ' flowers of two kinds : 

 one perfect but sterile ; the other destitute of calyx, corolla, 

 and stamens, and fertile.' The fertile flowers consist there- 

 fore solely of the legume." It is needless to state that a 

 legume is no part of a flower. It is not explained why the 

 perfect flowers are supposed to be invariably sterile, or 

 how the "legume" could receive pollen from the perfect 

 flowers. Foerste says : "It is impossible to say whether the 

 fertile flowers always were destitute of other floral envelops 

 and organs or not." Then, speaking of the pollen of the 

 perfect flowers, he says: "How from this place it reaches 

 the recurved style of the fertile flower below, except by 

 dropping off, is a mystery. Perhaps the long, bristle-like 

 hairs on the subtending leaves and bracts serve as brushes. 

 But even then it may be remarked that at least the earlier 

 legumes seem already fertilized." From the above we may 

 conclude that whether these legumes arose from perfect or 

 cleistogamous flowers, or both, does not appear, though it is 

 not improbable that the species has cleistogamous flowers. 



Foerste infers from the horizontal position of the banner 

 that: " Any insect visiting this flower will therefore receive 

 the pollen on its upper side." This is not true of the 

 Calliopsis, mentioned above. In fact there are a number of 

 flowers, such as Gerardia, Gratiola and Viola, whose normal 



