TfltB Pl.AS-T WoW.D 



merly united Corsica and Sardinia and constituted, till relatively 

 recent times, with the adjacent islands, a continental area con 

 tinuous with northern Africa 



Fischer in a recent study of the colors of flowers as influenced 

 by action of light (Flora, XCVIII, 1908) ascertained that va- 

 rious plants with red or blue colored flowers, e. g. species of Cy- 

 donia, Campanula, Digitalis, Aconitum, Fuchsia, produce only 

 small quantities of coloring matter in darkness, while plants with 

 yellow flowers, e. g species of Geum, Ranunculus, Chelidoninm, 

 Glaucium, exhibit but seldom such a diminution of floral color- 

 ing under like canditions 



The investigations of Blaauw on the ruhtiin between the 

 intensity of light and the length of illumination in certain photo- 

 tropic curvatures indicate that a definite quantity of light is 

 required to produce a reaction. The essential condition foi the 

 production of a phototropic curvature is the supply of a definite 

 quantity of radiant energy, and whether this quantity is sup- 

 plied in a short or a long time is a matter of indifference. 



From a review by Lind of a work by Galloce on the ecology 

 of Danish lichens (1908) the following abstract will serve to indi- 

 cate the essential features of this noteworthy contribution. The 

 author first discusses the general effect of water and light on 

 lichens, maintaining that their vegetative activity is but slightly 

 affected by difference of seasons. In following chapters he takes 

 up the various habitats of lichens in Denmark, namely, downs, 

 heaths, moors, woods and stones. Taking these habitats in 

 order : 



1. The sands of the seashore are destitute of lichens, most 

 likely on account of excess of salt; dunes in process of formation 

 support a very few species, and grass-covered downs a larger 

 number. As protection against intensive light lichens growing on 

 unsheltered soil either develop a brown pigment in the cortex, 



