II CARYOPHYLLACE.E 113 



S. media (Chickweed). — Some of the stamens are 

 generally more or less suppressed, being thus reduced 

 from 10 to 8, 6, or even 2. The violet anthers 

 ripen about the same time as the stigmas. If not 

 already visited by insects, the flower is almost sure to 

 fertilise itself when it closes. According to Celakovsky, 

 the variety Borcearia is cleistogamous. Bateson has 

 made some experiments with seeds from cross-fertilised 

 and self-fertilised flowers. The former were found to 

 be more vigorous in the proportion of 100:91. A 

 remarkable peculiarity of the Chickweed is, that while 

 the rest of the plant is glabrous, there is a line of com- 

 paratively large hairs running down the stem, and a few 

 long ones on the leaf-stalks. Bentham says of this line 

 of hairs that they "run down one side of the stem." 

 This does not exactly express the case. The leaves are 

 opposite decussate, i.e. each pair is opposite and at 

 right angles to the pairs immediately above and below. 

 The bases of the two leaves form a small cup. In many 

 cases a flower-stalk rises between the leaves. The line 

 of hairs is always on the side opposite the flower, and 

 changes its place, therefore, at each node. The stalks of 

 the leaves are somewhat hollowed above, and their edges 

 are fringed with long hairs. These and the hairy ridges of 

 the stem are easily wetted, and retain for some time the 

 rain that falls on the leaves. It is said to be absorbed 

 by the lower part of the hairs. It is probable that the 

 line of hairs serves to conduct the rain-water from each 

 cup to the one below.-' These hairs are full of sap, and 

 act quite differently from the dry hairs, by means of 

 which so many plants protect themselves against too 

 rapid transpiration. 



Seeds of Stellaria media are among the most com- 

 mon in recent geological strata. Mr. Clement Eeid 

 cites it from various localities from preglacial to 

 neolithic times. 



^ Lundstrom, Ad. Nov. Upsal. 1884-85. 



