296 



BRITISH FLOWERING PLANTS 



CHAP. 



up to the level of the stigma, so that in the absence of 

 insects it fertilises itself. The leaves are bright green, 

 with spreading hairs. Fig. 189 represents a flower of 



M. versicolor when just 

 opened. It will be ob- 

 served that the pistil pro- 

 jects above the corolla and 

 stamens, so that it must 

 be touched first by any 

 insect alighting on the 

 flower. Gradually, how- 

 ever, the corolla elongates, 

 carrying up the stamens 

 with it, until at length 

 they come opposite the 

 stigma, as shown in Fig. 

 190. Thus, if the flower has not already been fertilised 

 by insects, it is almost sure to fertilise itself. 



Fig. 190. 

 versicolor. Young 



Fig. 189. 

 Fig. 189. — Myosotis 



flower. 

 Fig. 190. — Older flower ; nrnch enlarged 



a, anther ; Cft, calyx ; co, corolla ; ■ 

 nectary ; oy, ovary ; st, stigma. 



Anchusa 



Homogamous bee flowers. Corolla-tube straight, with 

 honey at the base. Nuts attached by the broad end. 

 Two species occur in Britain, but both are rare, and 

 have presumably been introduced by human agency. 

 A. officinalis has terminal forked spikes, A. semper- 

 virens short axillary spikes. 



A. oificinalis. — The corolla is at first violet, then deep 

 blue. The entrance to the tube is guarded by five hairy, 

 closely fitting scales. Immediately below them is the 

 stigma, and about the middle of the tube are the 

 anthers, so that visiting insects touch the stigma first 

 and then the anthers. The corolla eventually detaches 

 itself and falls ofi", carrying some of the pollen with it, 

 and thus, in the absence of insects, fertilising the stigma. 

 In some places, besides the usual complete flowers, 

 others occur in which the stamens are rudimentary. 

 The flowers difi"er also in size and in the exact position 

 of the stamens, which, according to Schulz and Warming, 



