MR. A. W. BENNETT ON CLEISTOGAMIC FLOWERS. 275 



cullata, one pair of anthers being closely adpressed to the stigma. 

 The ovary is slightly hairy, the style very short and curved in a 



downwards. This 

 was the structure in two flowers that I examined. In two other 



(in the early 

 part of October) , the structure was very nearly the same as in the 



normal perfect flowers, except that the petals were small, trans- 

 parent, and colourless. The stamens had sessile anthers sur- 

 mounted by a transparent colourless prolongation of the connec- 

 tive, the style was erect and elongated, and the stigma bent at right 

 angles. There was no indication that fertilization had been 

 accomplished in these flowers. I observed no flowers in any in- 

 termediate stage between these two kinds of closed flowers. I 

 could not detect any tendency of the ripe capsules to bury them- 

 selves in the earth, as is stated, by D. M tiller, Vaucher, and Lecoq, 

 to be the case with those of V. odorata. 



V. sagittata, Ait. (North America). — The cleistogamic flowers 

 present considerable resemblance in appearance and in position 

 to those of V. cucullata, but are somewhat smaller. In the 

 flowers examined by me there were only two fertile and one 

 abortive stamen ; the two fertile ones have long filaments and 

 large hood-like prolongations of the connective, which adhere 

 firmly to the stigma even when the capsule has attained a consi- 

 derable size ; the very short style and stigma are depressed in the 

 hollow of the obovate ovary. The anther-lobes are approximate, 

 and evidently dehisce by terminal pores. The corolla is alto- 

 gether wanting. Both in this species and the next the capsules 

 contain a considerable number of unfertilized ovules. 



V. elatior, Fries (Central Europe). — The cleistogamic flowers 

 are borne in the axils of the leaves on the erect stem. In 

 the single one which I have had the opportunity of dissecting, 

 the five sepals are of a purple colour. There are only two fertile 

 stamens, which are attached to the bases of the two anterior 

 sepals, and resemble in all important points those of V. cucullata. 

 I observed no barren stamens. The short semicircular style and 

 flat stigma altogether resemble those in the species already de- 

 scribed. 



OXJLLIS. 



O. Acetosella, Linn.— The cleistogamic flowers are produced 

 abundantly in the summer and autumn, in the same position as 



