1893.) _ Briefer Articles. — 275 
BRIEFER ARTICLES. 
Difference between the common salt-wort and the Russian thistle.— 
Farmers’ Bulletin no. 10, of the Department of Agriculture, on the 
Russian thistle and other weeds, has aroused some interest in the 
distinctive differences between the harmless saltwort Salsola Kali L. 
and the noxious Russian thistle Sa/sola Kali L., var. tragus DC. 
The former has existed on the Atlantic coast for nearly a century at 
least and appears to be indigenous there and also in saline localities 
m the Black Hills. It has never been regarded asa troublesome 
weed. The variety “agus was introduced into South Dakota from 
Russia about seventeen years ago and is now justly regarded as the 
Worst weed in the northwest. 
The two forms appear very much alike but it is a matter of impor- 
gn that they should be distinguished. 
The original description of the variety is as follows: “@ Zragus, 
suberecta glabra viridis, alis subbrevibus subroseis vel roseis.”—DC. 
a eter Xt is given here in full because De Candolle’s 
; addi fomus 1s not as available to all botanists as one might wish. In 
. — to these characters the following may aid in distinguishing 
“wy from the species: The species S. Kaii does not become 
- ed or magenta colored at maturity. The middle bract, ora 
— leaf subtending the floral bracts, is usually much longer 
™ ae ha The calyx is dull white or slightly rose-colored and 
Wilting as wing on the back of the calyx lobes is thick and com- 
e idee less prominent than the ascending lobe. . 
turity on rt Aad becomes rose-colored or bright magenta at ma- 
exposed to ‘shee and more or less on the branches and all parts 
ONE appears 0 nek The bracts are nearly equal, or at least no 
T than ike. ved throughout the plant to be two or three times 
right ooh “he The calyx is membranaceous and nearly 
we thin and are “any red. The wings on the back of the calyx lobes 
All of these cha uch larger than the ascending lobes. oe 
- Coloris eee vary. Otherwise there would be aspecific dif- 
Of light ang moistur 
Constant, 
omparatively little value under different conditions 
€ but the characters of the calyx are reasonably 
It 
and care op expected along railroads in all parts of the north- 
0 seed ould be taken to kill it in these places before it goes 
mes established.—L. H. Dewey, Washington, D. C. 
