II LENTIBULARIACE/E 275 



aquatic plants, the flowers rise above the water, aii 



Fig. 174. — Utricularia vulgaris, a, flower seen from the side ; I, flower seen from 

 the front ; c, ovary and pistil ; d, stamen ; e, part of leaf showing a bladder. 



Fig. 175. — Utricularia vulgaris. 1, The flower, natural size. The dotted line shows 

 the position which the spur takes on the downward pressure of the under lip. 2, 

 Stamens and pistil shortly before the opening of the bud, viewed from under- 

 neath. 3, The same, viewed from the side. 4, The same, viewed from above. 

 5, The same, from a newly opened bud, viewed from the side. Tlie lobe of 

 the stigma is bent downwards. 6, The same, viewed from underneath. 7, The 

 same, viewed from above. 8-10, The pistil, after an outward irritation upon the 

 lobe of the stigma, and after the withdrawal of the corolla, in consequence of 

 which the stigma lobe, unimpeded by the corolla, has strongly turned itself 

 upwards. 



indication of their originally aerial condition. We have 



