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F. TRACY HUBBARD 
viridis var, typica Posp. Fl. Oesterr. Kiistenl. i: 51 (1897) [an var. 
typica Beck?]. S. viridis var. major (Gaud.) Posp. 1. c. i: 51 (1897). 
Chaetochloa viridis (L.) Scribn. U. S. Div. Agrost. Bull. 4: 39 (1897): 
Scribn. & Merr. U. S. Div. Agrost. Bull. 21: 19. f. 8 (1900): Nash, in 
Britt. Man., ed. i, 90 (1901); ed. 3, 90 (1907). Panicum viride 
[subsp.] A. P. eu-viride Aschers. & Graebn. Syn. Mitteleur. Fl. 2^: 
76 (1899). P. viride [subsp.] A. P. eu-viride A. I. a. i. majus (Gaud.) 
Aschers.. & Graebn. 1. c. 2^: 77 (1899). P. viride [subsp.] A. P. eu- 
viride A. I. a. I. a. reclinatum (Vill.) Aschers. & Graebn. 1. c. 2^: 77 
(1899). P' viride [subsp.] A. P. eu-viride A. I. a. i. b. pygmaeum 
Aschers. & Graebn. 2^: 77 (1899). P. viride [subsp.] A. P. eu-viride 
A. I. b. nodiflorum (Saccardo) Aschers. & Graebn. 1. c. 2^: 77 (1899). 
Setaria viridis var. humifusa (Lej. & Court.) Wildem. & Dur. Prodr. 
FL Belg. 3: 885 (1903). Panicum viride var. fallax (Bruhin) Dalla 
Torre & Sarnth. Fl. Tirol. 6^: 157 (1906). Setaria viridis subsp. eu- 
viridis (Aschers. & Graebn.) Briq. Prodr. Fl. Corse i: 68 (1910). 
S. italica subsp. viridis (L.) Thell. in Mem. Soc. Sci. Nat. Cherb. 38: 85 
(191 1). S. viridis var. australis F. M. Bail. Compr. Cat. Queensl. PI. 
611 (1913)- 
An extremely variable species frequently approaching S. italica or 
S. verticillata in appearance. From the former it may be distinguished 
by the spikelets being articulate below the glumes and easily shelled 
out — entire — when nearing maturity, leaving a little cup at the end 
of the pedicel, whereas 5. italica is articulate above the glumes and 
shells out the fruit only. Some few specimens show intermediate 
characters and point toward hybridity. S. viridis is considered by 
many to be the origin of S. italica which may well be the case, but 
to-day the two seem to be readily separated by the above-stated 
character. From S. verticillata it is at once distinguished by the 
antrorse barbs of the setae: S. verticillata has the setae retrorsely 
barbed. 
There are many forms of the species which in most instances are 
not clearly differentiated and which pass into each other too thoroughly 
to seem worthy of nomenclatorial designation. Size of plant, size of 
panicle, color and length of setae are all variable, but not consistently 
enough so to separate along these lines. Seed color is usually the same, 
— when fully mature, — a dull straw-drab with darker mottlings, 
though immature it ranges from whitish-green through shades of 
green and yellowish-green to straw. 
