EUPHORBIA VI ROSA AND ALOE DICHOTOMA 
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4. The water-storing tissue of the primary parts of the stem of Aloe 
clichotoma Linn, from Namaqualand is traversed by a network of intercellular 
spaces which are formed, in the first place schizogenously, but for the most 
part according to the lysigenous method. 
5. The air-cavities in the secondary ground-tissue are formed schizo- 
genously as a result of tensions set up during the increase of girth of the 
stem. 
6. In the Aloe-stem there are thus two distinct systems of aerating 
tissue. 
7. In both plants we see examples of a combination, within one and the 
same tissue, of the two functions of water-storing and of air-storing. 
