CARYOPHYLLEAE 



133. Krascheninikovia Turcz. 

 Kuhn states that cleistogamous flowers occur in this genus. 



185 



134. Arenaria L. 



Flowers small and white, homogamous or protandrous, with half-concealed 

 nectar secreted in the usual place. 



461. A. serpyllifolia L. (Herm. MuUer, ' Weit. Beob.,' II, p. 226 ; MacLeod, 

 Bot. Jaarb. Dodonaea, Ghent, vi, 1894, p. 161 ; Kirchner, 'Flora v. Stuttgart,' p. 754 ; 

 Schulz, 'Beitrage,' I, p. 19, II, p. 47.) — In this species the stamens and stigmas 

 mature simultaneously, and in sunshiny weather drops of nectar can be seen in the 

 base of the flower. Schulz also observed female flowers on gynomonoecious, rarely 

 on gynodioecious plants. In hermaphrodite flowers the stamens are frequently 

 reduced in number; and automatic self-pollination by contact of stigmas and 

 anthers is unavoidable. 



Fig. 55. Arenaria bijiora^ L. (after Herm. Miiller). A, Flower in the first (male) stage. B. Flower 

 (with 5 styles) in the second (female) stage, seen from above. C. Stamens and nectaries of the same 

 flower. 



Visitors. — Herm. MuUer observed 2 small short-tongued bees — Sphecodes 

 ephippius L. 5, and Halictus lucidulus Schenck $, skg. — both capable of effecting 

 cross-pollination. 



MacLeod saw a hover-fly in the Pyrenees (Bot. Jaarb. Dodonaea, Ghent, 

 iii, 1891, p. 377). 



In Dumfriesshire, a hover-fly and Thrips have been recorded (Scott-Elliot, 

 'Flora of Dumfriesshire,' p. 26). 



462. A. biflora L. (Herm. Miiller, ' Alpenblumen,' pp. 185-7; Schulz, 

 ' Beitrage,' II, pp. 47-8.) — The white flowers are protandrous, but the periods of 

 maturation, not only of the outer and inner stamens, but also of the inner stamens 



