ON" A VARIETY OF^ HIEllAClUM CESIUM. 3G1 



In its inflorescence it agrees closely with the plant common upon 

 the limestone scars of the North of England, figured by Smith in 

 ' English Botany,' t. 2082, under the name of H. muroriun, and which 

 we now look upon in this country as our typical H. cccsium; but it 

 differs from this cons^^icuously in its leaves, which are as glaucous 

 as in any native Hieracium, and in shai3e much more lanceolate, 

 with remarkably large acute teeth. As has been already pointed 

 out by Backhouse in his ' Monograi^h,' and by Dr. Boswell in 

 'English Botany,' this English casiiun is by no means absolutely 

 identical with the common Scandinavian plant first called by that 

 name by Fries. Type sj)ecimens of the latter are given under 

 No. 86 of the Fasciculus of dried specimens of Hieracia, issued in 

 1866 by Fries. It comes about midway between the English ccesium 

 and ordinary vuhjatum, receding from the former in its less rosulate 

 narrower leaves and more numerous and smaller flower-heads. In 

 order to make the matter plainer I will give short comparative 

 descriptions of the three forms. 



H. ccBsium, the typical plant of Fries, * SymbolaB,' p. 112, and 

 ' Epicrisis,' p. 92, No. 86. — Whole plant 1-1^ foot high. Developed 

 leaves 4-6 in a radical rosette cotemporary with the flowers : blade 

 grey-green, thin in texture, oblong, acute, 2-3 rarely 4 in. long, 

 1-1|- in. broad, narrowed to the petiole except in the primordial 

 leaves, furnished with 3-4 deltoid or lanceolate teeth of moderate 

 size on each side in the lower half, with a few soft crisped hairs 

 near the margin ; petiole shorter than the blade, moderately hairy. 

 Stem bearing one large stalked toothed lanceolate leaf above the 

 base and often another small one higher up, and 4-8 corymbose 

 heads, all on long peduncles, with a little white stellate down and 

 very few short black bristly hairs without glands at the tip. 

 Involucre globose, in flower about ^ in., finally ^ in. diameter, 

 \ in. long ; phyllaries linear, acute, dark olive in the centre, paler 

 towards the margin, with a keel of black bristly hah's without 

 glands and in the lower part white ones intermixed, without any 

 white floccose tomentum. Styles livid. Outer flowers f in. long. 



H. ccEsium, var. Smithii ^=H. cmsium, Engl. Bot., 3rd edit., 

 tab. 847. — Whole plant 1-1 i foot high. Developed leaves about 

 half a dozen in a radical rosette cotemporary with the flowers ; 

 blade greyish green, thin in texture, oblong or ovate-oblong, acute, 

 2-4 in. long, 1^-2 in. broad, often narrowed suddenly to the base, 

 furnished with a few small teeth on each side and a few short soft 

 hairs near the margin ; petiole rather shorter than the lamina, 

 densely pilose. Stem without any leaves or furnished with a single 

 small one near the base ; bearing usually 3-4 corymbose heads, aU 

 on longish peduncles, with a little white stellate down and a few 

 black bristly hau's, not gland-tipped. Involucre finally ^-f in. 

 diameter, ^ in. long ; phyllaries linear, acute, with many black 

 bristly hairs mostly without glandular tips. Styles livid. Flowers 

 often an inch long. This is the Giggleswick cmaium spoken of in 

 Backhouse's ' Monograph,' and the ccesium, var. a. /jemthium, de- 

 scribed by Dr. Boswell. It is frequent in the limestone clift's of 

 Yorkshire, Durham and Derbyshire, and ranges in Britain from 



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