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the ground beneath a large redwood into the form of a trough at 

 the lower end of which he has placed a barrel, and I have it on 

 good authority that in this primitive manner he obtains sufficient 

 water for his needs. However picturesque a "tree-well" may 

 appear, I believe, as does also Prof. W. R. Dudley, of Stanford 

 University, who has studied these conditions for several years, 

 that a receptacle for the water which the tree " combs " out from 

 the fog might be so placed that it would catch nearly all of the 

 water thus retained, in a manner analogous to that employed by 

 the chopper, and from data thus obtained some estimate of the 

 total fog precipitation in a redwood forest might be had. It is 

 hardly necessary to say that in any such calculation the density 

 of the fog, the rate of the wind, as well as the character of the 

 forest, and other factors would have to be considered, all of 

 which could be worked out for each time of calculation. 



A comparative study of the amount of water which different 

 species of forest trees are able to take from fog could not fail to 

 be of interest, and may be found to be of great moment in the 

 life processes of the denizens of the region. And may it not be 

 that the increased amount of the total precipitation brought about 

 especially by the redwoods as just described, and its more uni- 

 form distribution throughout the year, will prove to be an im- 

 portant and possibly a determining factor in reforesting a denuded 

 redwood area ? 



ARE THE LEAVES OF "SIMPLE-LEAVED 

 AMPELOPSIS " SIMPLE? 



By Byron D. Halsted ' 



A vine of Ampelopsis cordata Michx., growing upon my house 

 piazza has interested me during the autumn days by the reluctant 

 way in which it drops its leaves. It keeps them green for weeks 

 after the leaflets of the American ivy \Parthenocissus quinquefolia 

 (L.)] have taken on a blaze of colors and gone. The last-named 

 vine, as is well known, has its leaves compounded of five leaflets 

 and accommodates their departure by providing each leaflet with 

 a "letter of dismissal" that is composed through the season's 



