1 882.] Forests — their hi j u n 'fall. 19 



so far as I am aware, the occurrence of both homogone and tri- 

 morphic species gives some reason for looking for still others 

 which are dimorphic. In writing this I am perfectly aware that 

 Hildebrand 1 has examined a few herbarium specimens of O^oio- 

 lacea, finding eight long-styled, three short-styled, and one mid- 

 styled plant in the -twelve specimens examined. The constant 

 lack of correspondence in our specimens between the sets of 

 stamens which should correspond, however, leads one to wonder 

 if a mistake may not have been made, especially since a slight 

 discrepancy exists between the numbers cited and the summary, 

 in the paragraph cited. 



Both the long and short-styled flowers are visited by small bees in 

 considerable numbers, the more common being Nomada bisignata, 

 Ccratuia dupla, Augochlora pnra y an Osmia, and several species 

 of Halictus. These insects are attracted by the nectar which is 

 secreted, apparently, by the papillose bases of the petals, and 

 which is protected from rain, &c, by pubescence on the styles in 

 the long-styled flowers, and on the filaments in the other form. 

 As a result of these visits, some flowers of both kinds produce 

 capsules, which are by no means uncommon, although by far the 

 greater number fall away without bearing any fruit. 



FORESTS— THEIR INFLUENCE UPON CLIMATE AND 

 RAINFALL. 



BY J. M. ANDERS, M.D., PH.D. 



'THAT there exists some sort of relation betwixt forests and 

 A conditions of climate, perhaps most observers would be ready 

 to concede. Many attempts have been made to explain how forests 

 affect atmospheric states, but there is great diversity of opinion 

 on the subject, and, indeed, the question to-day remains some- 

 what involved in obscurity. As every one knows, there was a 

 time when forests were considered almost inexhaustible. It is 

 also a well-known fact that the destructive hand of man began, 

 centuries ago, to fell rapidly these abundant forests, and changes 

 of climate and fertility of the soil have, in numerous regions, 

 been attributed solely to this denudation of the land. On exam- 

 ining the literature of the subject, it is found that the balance of 

 ^onatsber. Berlin Akad., June 21, 1866, p. 357. 



