NEW OR NOTEWORTHY SPECIES. 161 
notably small-bracted : bracts of the involucre in 3 or 4 series, 
all narrow and obtuse, the inner and longer ones with a dis- 
tinet mid-nerve and thin-hyaline margins, only the tips her- 
baceous throughout: achenes long, slender, distinctly cla- 
' vate, constricted at summit under the pappus and very 
definitely 15-striate, canescent with a rather closely appressed 
pubescence: pappus very bright white, fine and fragile. 
This is the southern plant referred by Gray to 5: humilis, 
and forming a part of Prof. Porter's S. Purshii. But the ex- 
cellent characters of the loose open racemose inflorescence, 
the half-hyaline and completely glandless involucral bracts, 
and particularly those of the clavellate 15-striate achene, are 
very decisive of its specific rank. The true S. Purshi has 
altogether another sort of inflorescence, an achene more 
turbinate than clavate, with ten ribs instead of fifteen fine 
strie, and with a pubescence less dense, and that hirtellous 
rather than silky. This diagnosis is drawn from beautiful 
and thoroughly mature specimens collected last autumn, near 
the Great Falls of the Potomac, by Mr. D. Le Roy Topping. 
SoLIDAGO DECUMBENS. Stems clustered about the summit 
of a strong perpendicular root, stout, decumbent, from a few 
inches to more than a foot high, usually dark red, sparsely 
puberulent, as is also the foliage: lowest leaves from spatu- 
late-obovate to oblanceolate, obtuse or acutish, more or less 
distinctly serrate toward the summit, upper cauline leaves 
similar, but few and reduced, all scabrous on the margin : 
inflorescence interruptedly thyrsoid: heads large; bracts of 
involucre somewhat glandular-viseid, linear, obtusish, of 
firm texture and carinate-nerved, forming about 3 series, the 
outer and shorter rather subulate-linear than linear: achenes 
subcylindric, but with 5 rather prominent angles and as 
many intervening strize, loosely strigose-hispidulous; pappus 
very strongly barbellate scabrous. 
Very common species of the Rocky Mountains of Colorado 
ànd northward, in subalpine and alpine situations, but occu- 
