CARYOPHYLLEAE 



187 



pollination can take place early. There are usually only three stamens, more rarely 

 five, four, or two. A green fleshy nectary is situated at the base of each stamen. At 

 the beginning of anthesis, when the anthers are dehiscing, the styles with their incom- 

 pletely developed stigmas are erect. The stamens, however, are so curved inwards 

 as to bring the anthers immediately above the stigmas, so that when these are mature 

 automatic self-pollination must result from the fall of pollen. It also often takes 

 place in the closed flower. Dehisced stamens gradually incline outwards, and the 

 stigmas spread out more and more. Warnstorf says that the outer stamens ripen earlier 

 than the inner ones ; their filaments are longer, and their bases are provided with 

 yellow nectaries. The anthers are yellow, and after dehiscence undergo a rotation 

 through 90 , so as to become horizontal. The pollen-grains are golden yellow, 

 regularly dodecahedral, and closely beset with short spines; average diameter 37 fi. 



Besides hermaphrodite flowers, female ones have also been observed, distributed 

 gynodioeciously, or more rarely gynomonoeciously. The ordinary flowers are 

 locally e. g. in Denmark 

 homogamous, or even pro- 

 togynous. 



Visitors. Herm. 

 Miiller observed a Muscid 

 Anthomyia sp. 5 and 3 

 bees, i. e. Andrena gwynana 

 K. 5, skg. ; A. parvula K. 5, 

 skg. ; and Halictus sp. $, 

 skg. 



136. Stellaria L. 



Flowers white, protan- 

 drous, homogamous, or pro- 

 togynous, with half-con- 

 cealed nectar secreted at 

 the bases of the stamens. 



467. S. graminea L. 

 (Herm. Miiller, 'Fertilisa- 

 tion,' pp. 133-4, 'Weit. 

 Beob.,' II, p. 227; Knuth, 

 ' Bl. u. Insekt. a. d. nordfr. 

 Ins./ p. 45, ' Bloemenbiol. 

 Bijdragen'; Kirchner,' Flora 

 v. Stuttgart,' p. 238 ; Ludwig, 

 Bot. Centralbl., Cassel, iii, 

 1880; Schulz, 'Beitrage,' I, 

 p. 20, II, pp. 50-1.) In 

 this species the five nec- 

 taries are in the form of 

 green, fleshy ridges at the 



Fig. 56. Stellaria graminea, L. (after Herm. Miiller). i. Flower 

 in the first half of the first (male) stage : the five outer stamens have 

 curved inwards, and their anthers are covered with pollen. 2. Flower 



in the second (female) stage : all the anthers are empty and shrivelled ; 

 the styles have spread out and curved backwards, thus turning upwards 

 their papillose sides, a 1 and a 2 , outer and inner stamens; n, nectaries 

 si, stigmas. 



bases of the five outer stamens. The flowers are 



