

226 MISSOURI BOTANICAL GARDEN 



most 



d 



Before leaving this subject, I will refer briefly to the 

 anomalous C ochleostema . It is the most magnificent mem- 

 ber of the Commelinaceae, with flowers two or two and 

 one half inches in diameter, sepals and petals highly 

 colored and patent, androecium of six elements in two 

 whorls, fertile stamens 3, 1 from outer and 2 from inner 

 whorl, forming a pedicelled staminal column with the 

 anthers all spirally twisted and dehiscing longitudinally ; 

 one horizontal at the base of a corniform hood formed by 

 involute, petaloid outgrowths from the other two which 

 inclose all three stamens. 



The habit of this most complex flower is almost exactly 

 identical with that of some of the zygomorphic, apically 

 dehiscent forms, as for instance, 8. rostratum, the form 

 of the perianth and the position of the pistil being the 

 same and the staminal hood simulating almost exactly 

 the arcuate anther. Loew and Appel in Knuth's Hand- 

 buch devote considerable space to a discussion of this 

 remarkable plant and I shall add the further suggestion 

 that the fragrant, nectarless flowers may be adapted to the 

 larger Apidae which seek the hairs of the staminodia or 

 other juicy portions of the flower and effect pollination in 

 the same way as in apically dehiscent forms. 



When I first saw a habit figure of Cochliostema I thought 

 it an apically dehiscent form with one large anther similar 

 to S. rostratum. If the suggestion just offered prove the 

 right one, we have a most remarkable case of parallel 

 adaptation. 



Nothing is known of the pollination of Monochoria. 

 Pontederia is visited for nectar and sometimes for pollen 

 by large bees. Heteranthera has been described as a pollen 

 flower. The secretion of nectar is not abundant if it occurs 

 at all in Eichomia> at least when grown in the north. On 

 E. azurea, Miiller observed only bees belonging to the 



