Page:An introduction to physiological and systematical botany (1st edition).djvu/143

 Rh Bot. t. 1071, as well as to numerous beautiful productions of the Cape of Good Hope.

7. Radix articulata, or granulata. A Jointed or Granulated Root agrees very much with those described in the last section. The Oxalis Acetosella, Wood Sorrel, ''Engl. Bot. t. 762, and Saxifraga granulata, White Saxifrage, t.'' 500, are instances of it. The former has most affinity with scaly bulbs, the latter with solid ones.

It is evident that fleshy roots, whether of a tuberous or bulbous nature, must, at all times, powerfully resist drought. We have already mentioned, p. 41, the acquisition of a bulb in ''Phleum pratense, Engl. Bot. t.'' 1076, whenever that grass is situated in a fluctuating soil, by which its vital powers are supported while the fibrous roots are deprived of their usual supplies. In this state it becomes the Phleum nodosum of authors; but on being removed to a thoroughly wet soil, it resumes the entirely fibrous root, and luxuriant growth, of ''Ph. pratense''. I have also found Alopecurus geniculatus, t. 1250, (an