Korschinsky distinguishes clearly and definitely be- 

 tween the principles of Heterogenesis and Transmutation 

 (gradual transformation through natural selection in the 

 struggle for existence), and in so doing comes to a com- 

 plete denial of Darwinism. N L' , . ' 



The other naturalist who has dealt Darwinism a tell- 

 ing blow is the botanist of Graz, Professor Haberlandt. 



He published some very interesting observations and 

 experiments in the "Festschrift fuer Schwendener" (Berlin 

 1899, Borntraeger). They are concerned with a Liane 

 javas of the family of mulberry plants (Conocephalus 

 ovatus.) The free leaves possess under the outer layer, a 

 tissue composed of large, thin-walled, water-storing cells; 

 flat cavities on the upper side, having, furthermore, organs 

 that secrete water, which the botanist calls hydathodes. 

 These are delicate, small, glandular cells over which are 

 the bundles of vascular fibres (leaf-veins) that convey the 

 water to them; over these in the top layer are so-called 

 water-crevices through which the water can force itself to 

 the outside. It is unnecessary to enter upon a closer ex- 

 planation of the anatomical structure of these peculiar 

 organs. The water which is forced upward by the root- 

 pressure of the plant is naturally conveyed through the 

 vascular fibres into the leaves and at every hydathode the 

 superfluous water oozes out in drops, a phenomenon which 

 one can also very nicely observe e.g. on the "Lady's cloak" 

 (Alchemilla vulgaris) of the German flora. A portion of 

 the night-dew must be attributed to this secretion of water. 

 On the Liane, then, Haberlandt observed a very consider- 



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