NATURAL HISTORY OF PLANTS. 



are higher up on this basilar portion of the stem, each becoming 

 in turn a leafy aerial branch ending in an inflorescence ; later 

 on, swelling at the base, and then giving up its juices to supply 

 the evolution of the buds axillary to its first leaves. Thus the 

 rhizome of the Columbine gradually ramifies, while the primitive 

 root, after having at first formed a tolerably large tap-root, gradually 

 becomes hollow and withers, till it has entirely disappeared, and the 

 plant is wholly nourished by the adventitious roots, which appear 

 at each period of vegetation at the base of the ascending axes. 

 Many perennial Banunculacece resemble this, and belong to the group 

 of plants with definite axes evolved successively. 



Xanthorhiza apiifolia Lher.,' though of very different habit, and with 

 very small flowers which at first sight hardly recall those of the 

 Columbine,- presents nearly the same floral 

 organization, and may be considered a 

 smaller type of this,^ from which the only 

 essential point of diff'erence is the smaller 

 number of staminal whorls in the former. 

 The perianth (fig. 13) is formed of five 

 caducous sepals, as a rule quincuncially 

 imbricated in the bud, and of five smaller, 

 fleshy, glandular petals, contracted at the 

 and dilated above into a cordate somewhat 



Xanthorhiza apiifolia. 

 Fig. 13. Fig. 14. 



Flower. Petal. 



base into a narrow claw, 

 concave limb (tig. 14). 



The stamens are often ten in number, arranged in two whorls, so 

 that five are opposite the sepals and five opposite the petals ; but 

 we often find the parts of one whorl more or less abortive. Each 

 stamen consists of a hypogynous filament, and a basifixed flattened 

 bilocular anther, dehiscing by two longitudinal lateral clefts, rather 

 turned inwards than outwards. The gynajceum is often formed of 

 five free carpels opposite the petals, each composed of a unilocular 



' Xanthorhiza Maesu, ex SCHEEB., Oen., 727, 

 11.1851.-LAMK., III., I. 854; DC, P/orfr., i. G5. 

 — Si'ACli, Suit, a Buff., vii. 407. — Endl., Gen., 

 n. 4803.— A. Gray, ///., t. 17.— H. H., Gtn.,9, 

 n. 29, — H. I5n. Adamoiiia., iv. 44. — Xanthorhiza 

 apiifolia, Luva., Stirp. Nov.,'7i),t. 38. — Duham., 

 Arbr., last ed., iii. t. 37. 



- This has been generally placed near Acicea 

 or Faonia. A. -L. de Jussiku {Gen. 234) says 

 on this plant — " CimicifugcB njinis." 



' Pateb {Organog., 247). " There are," says 

 he, " only very minute diil'orenccs between tlio 

 flowers of Aqtiilegia and Xanthorhiza, con- 

 sisting, as they do, in the dill'erent ninnber of 

 whorls in the androceuni on the one liand, and 

 in the form of the jietals on the other; and I 

 can with difficulty understand why botanists have 

 placed these two genera in different sections. 



