THE HAIRS. 97 



radiating at the apex ; those which ramify at the base, and 

 appear in bundles, as in the Marsh-mallow, (pi. 3, H. ) ; 

 the brush-shaped (en goupillon,) which are knotted 

 hairs, each knot of which produces a whorl of hairs, 

 as in Phlomis ; and, lastly, shield-shaped, (en ecusson,) 

 which are hairs radiating from a common base, and all 

 united together in a horizontal disk attached by its 

 centre, as in Elcsagmis, (pi. 3, I.) 



4th. Needle-shaped, (aculeiformes.) I describe 

 under this name hairs which, instead of being formed of 

 a simple series of cellules, are formed of several agglo- 

 merated, as in cellular tissue ; and the union of which, 

 projecting from th^ surface, has the general form of a 

 hair. These organs are usually thicker than common 

 Lymphatic Hairs ; and several of them have a tendency 

 to blend either with the glanduliferous, or with stings. 

 There is not even any precise character by which they 

 may be distinguished, unless it be their softness, com- 

 pared with the stiffness of stings ; but as this character 

 admits of all intermediate degrees, it is really impossible 

 to distinguish with precision the needle-shaped hairs 

 from true stings. 



Lymphatic Hairs only arise from the parts of plants 

 exposed to the air ; thus, they are not found either upon 

 true roots, except at the moment of germination, or upon 

 the portions of stems or branches buried under ground, 

 or in any of the parts ot plants which grow under water. 

 They are frequently found upon young stems or branches, 

 and sometimes they remain even upon the trunk ; they 

 are common upon leaves, stipules, and the calyx, 

 especially upon their inferior surface; they are rarely 

 found upon the superior part when not upon the infe- 

 rior. This, however, is observed upon the seminal leaves 

 ■of the Nettle, and upon the common ones of Passerina 

 hirsuta. Sec. They are found also upon the petioles 



VOL. I. H 



