94 
readily distinguished by tbe naked eye. It is more nearly allied to 
P, dioica^ Magnus, but whether these two species are identical I can 
at the present moment hardly say. 
King's Lynn, Eng. Charles B. Plowright. 
Berteroa incana, placed by Bentham and Hooker under Alyss- 
um^ but known among other things by its bifid petals with expanded 
saccate bases, has appeared spontaneously in several places in our 
city. 
J 
In a field with the above I have found a fine plant of Sonchtis 
arvensts 
Providence, R, I. W. Whitman 
Rudbeckia MisSOuriensiS.— This is between R, hirta and R.ful- 
gida, but more closely allied to the latter. R, Hirta, as compared 
with fzdgida^ commences to flower three weeks earlier. When cut 
through longitudinally the receptacle is narrowly conical, almost lan- 
ceolate. The leaves are wide in proportion to length, and remotely 
edged with minute serratures. The stems and leaves are very rough. 
The habit is widely branching. 
R^ ftilgida begins to flower three weeks later, has a broadly ovate, 
somewhat triangular receptacle, narrow leaves, with remote toothed, 
.deeply cut edges, and the stems and leaves clothed with short, soft 
hair. The habit is somewhat erect. 
R, Missoiiriensis opens \yi\\\ fulgtda^ has still narrower leaves than 
fulgtda, and the receptacle is broadly ovate as 'in ///^^/V*:/, though 
more acute at the apex. But the narrow leaves are quite entire, and 
the whole plant more rough than even the rough R, hirta. There is 
a greater tendency in the ray-florets of R. Missouriensis to become 
*' quilled," as the florists term it, than, in tHose of the others. 
T. Meeham. 
Botanical Notes. 
Ilisto-Chcmistry of Plants,~\x\ an interesting contribution to the 
" histo-chemistry '' of plants {Monaishe/tc, v., 94) Herr Rosoll illus- 
trates the light that can be thrown upon vegetable principles by 
studying them microchemically in situ in the plant. The first plant 
mentioned is Helichrysum bracteatuni, the yellow flower-heads of 
which are well known as a variety of '* everlasting flowers." This 
yellow color is very persistent, but when the dried flower-heads are 
dipped into borax solution to which hydrochloric acid has been added, 
the involucral leaflets become of a beautiful ruby-red color. Further 
investigation showed this yellow pigment to be a hitherto undescribed 
quinone-like substance, which HerrRossoll has named '* helichrysm. 
In the younger leaflets it exists in combination with protoplasm, 
whilst in the older ones it has its seat in the residual cell contents. 
Helichrysin is soluble in water, alcohol, ether and organic acids; in- 
soluble in benzol, chloroform and carbon bisulphide; is colorea 
purple-red by mineral acids and alkalies; and is precipitated by me- 
tallic oxides and their salts as a red colored extract. The same 
