CHAPTER IX. 



NON-TYPICAL SHOOTS. 



Creeping shoots — Super-terranean types — Subterranean types — 

 Rhizomes — Monopodial rhizomes — Bracken and others — As- 

 cending rhizome of Primrose — Synipodial rhizomes — Thick 

 rhizomes as food reservoirs — Thin rhizomes ; stolons or soboles 

 — Subterranean stem-tubers — Potato — Other tubers — Arum — 

 Corms of Crocus, Colc/naim, Cyclamen, a,ud Ranunculus hulbosus 

 --Bulbs — Pseudo-bidbs of epiphytic orchids — Shoots in aquatic 

 plants — Rhizomes — Stolons — Submerged shoots with or without 

 floating leaves — Lemna-ty\>& — Types of Pistia, Aldrovandia, 

 and Salviiiia — Succulent plants — Succulent stems in Cactacese, 

 Euphorbia and Stapclia — Succulent leaves. 



A SECOND class of" non-typical shoots are characterised 

 by their habit of creeping away from the centre formed by 

 the parent plant or root, and pushing their terminal buds 

 some distance in a radial direction from the already 

 occupied and exhausted area from which they staited. 

 This they may do simply along the surface of the ground, 

 as in the case of the runners of the Strawberry, Ranun- 

 culus repens, Hieracium Pilosella, Ground Ivy, &c., or 

 beneath the surface as in the Rhizomes of Carex, Yellow 

 Flag, Equisetum, Bracken Fern, &c. The creeping Willow, 

 Salix repens, does either or both. 



In both sets of cases the object attained is to develope 



8—2 



