466 



the case is usually as follows in P. vulgaris : The flower is 

 homogamous, and self-pollination is prevented by the foremost 

 part of the stigma being very large and stretching far beyond 

 the anthers so that these latter are totally covered. The hind- 

 most part of the stigma is on the other hand small and some- 

 times divided into two (Fig. 9, B). The anthers open with a 

 longitudinal slit closely below the stigma. The proboscis of 



Fig. 9. Pinguicula vulgaris. 



A, Flower; the entrance is not well-drawn; it ought to be somewhat wider. B,A stigma, 

 the hindmost part of which has been divided into two lobes; p. pollen-grains. C, Longi- 

 tudinal section through pistil; the foremost part of the stigma has rolled backwards down 

 to the anthers. D, Pistil with the stigma, rolled backwards, and the two anthers, seen 

 from front. E, Different forms of hairs from the spur (see also H in Fig. 10). F, A glan- 

 dular hair from the inner wall of the spur; the head is seen also from above. (E. W. ; 

 1886). A, From Tromsø; В— F, From Godhavn in Greenland. 



the insect, when entering the flower, first touches the foremost 

 part of the stigma, and when withdrawn this part of the stigma 

 is bent aside, and the insect is furnished with pollen. After this 

 the elastic stigma again springs back and covers the anthers. 

 Owing to this circumstance self-pollination must be impossible, 

 but in the arctic specimens the case is different. Warming has 

 sometimes found the foremost part of the stigma rolled in 

 such a manner, that its upper surface was brought into close 

 contact with the pollen-masses (Fig. 9, D); this I have observed 



