250 Eue Warming. 



— in rare cases — so densely, that it becomes somewhat 

 pulvinate. 



C. caespitosum with its variety alpestre varies in the 

 same manner as C. alpinum (Sylvén, p. 300). It has some- 

 times very long stems. Cerastium Regelii I have only seen 

 divergently branched. 



At the apex of the shoots a kind of rosette is often 

 met with, in that the internodes here are short temporarily, 

 and a kind of winter-bud is developed, as for instance in 

 Cerastium alpinum; the youngest leaves and flower-buds of 

 the latter must thereby and by means of the densely villous- 

 haired leaves be provided with an excellent winter-covering 

 (Fig. 8, F). It is not always that such a shoot-development 

 appears. 



Similar features are met with in Arenaria ciliata. The 

 stems with elongated internodes may be erect, but may also be 

 more or less prostrate and entangled, covered with white 

 flowers. Pulvinate forms may develop, although not so 

 decidedly as in the Minuartia's and inSilene. In other respects, 

 it most resembles the latter in the form of its branches and 

 the position of its flowers. It may have several (apparently 

 lateral) flowers upwards along a long axis. I regard this as 

 a sympodium, but have observed cases which were doubtful. 



Vegetative propagation it appears does not generally 

 take place. Neither Thekla Resvoll nor I have observed 

 such in C. alpinum, although this species may have adventi- 

 tious roots (Fig. 8, G). Sylvén, however, mentions "sub- 

 terranean runners with scale-leaves (or scale-foliage-leaves)" 

 in C. alpinum. Nor has Thekla Resvoll found vegetative 

 propagation to take place in C. nigrescens (C. Edmonstonii). 



The seedlings. Sylvén found that seedlings of Cera- 

 stium alpinum when growing in nature hardly flowered 

 '"until after the lapse of 2 years." The seedlings of Arenaria 



