690 
Journal of Agricultural Research 
Vol. XXIV, Na 8 
tendency toward branching. They are light fuliginous to light yellowish 
in color; very noticeably torulose, hence decidedly variable in diameter, 
this dimension ranging from 5 to 10 /i, while the length often exceeds 
500 and usually septate at intervals of from 20 to 40 ju. 
The spores (PI. 16, Ca-q), borne in great abundance at the apices and 
geniculations of the distal portions of the fructifications, are straight or 
show a slight crescentic or sigmoid curve; rounded at both ends, the apical 
end often more broadly than the basal end, owing to a tendency toward 
tapering in the basal and juxtabasal segments; 12 to 19 ju in diameter by 
22 to 78 At in length; and i to 5 (usually 3 or 4) septate, the septa rarely 
associated with perceptible constrictions in the contour of the thin 
peripheral wall within which, at the point of attachment, the small dark 
hilum is readily observed. The conidia germinate readily in water, 
sending out a germ tube from one, or more usually from both, end 
cells. (PI. 16, Da-e.) 
Karsten and Roumegu^re (75) have described a fungus from Tonking 
growing apparently on the same host {Sporoholus tenacissimus, the host 
name given, being listed as a synon)nn of S. indicus in the Index Kewensis) 
and corresponding to Helminthosporium ravenelii in all details relating to 
habit, color, and structure of conidiophores, as well as to color, structure, 
and dimensions of conidia. This form, which they designated as a new 
species, H. tonkinense, and regarded as being related to H, ravenelii, is 
undoubtedly altogether identical with the latter. Nor can there be 
much question that the same holds true also of H, crustaceum described 
from Java by Hennings (5^) as forming dark crustaceous effuse tufts on 
the iiffiorescence of a species of Sporobolus. According to this botanist, 
H, crustaceum is related to i/. ravenelii but distinct on account of its 
conidia. Inasmuch as the latter are characterized as— 
Oblonge clavatis vel fusoidois, utrinque obtusis, rectis vel curvulis, 40-60X12-16 jw, 
3-5 septatis, baud c»nstrictis, fuscis— 
in all of which particulars the agreement with H. ravenelii is at least 
reasonably close, the writer is inclined to believe that Hennings's binomial 
should be regarded as a synon)nn until some evidence for Sie justifica¬ 
tion of a new species has been adduced. 
HELMINTHOSPORIUM SATIVUM P. K. & B. 
Helminthosporium acrothecioides Lindfors 1918, in Svensk Bot. Tidskr. v. 12, p. 227. 
Helminthosporium gramineum of E. C. Johnson, Massee, Palm, Eassi, not Rabenhorst. 
Helminthosporium inconspicuum of Peck, Atkinson, not Cooke & Ellis. 
Helminthosporium Sorokinianum Sacc. 1891, in Ztschr. Pflanzenkr., Bd. i, p. 236-239. 
Helminthosporium teres of Bakke, not Saccardo. 
Helminthosporium sp. of Beckwith, Bolley, Evans, Hamblin, Hungerford, McKinney, 
Stakman, Stevens, Waterhouse. 
Although the fungus to which it has appeared advisable to apply the 
binomial given by Pammel, King, and Bakke {104), probably is the 
species most frequently encountered by plant pathologists, it has been 
the subject of much confusion in the literature. This condition is 
largely attributable to the fact not hitherto generally recognized that 
it occurs on a number of graminaceous hosts, several of which, more¬ 
over, are affected by one or more congeneric parasites. As the specific 
characteristics of the latter have not Sways been clearly distinguished, 
and as the fungus und^ consideration shows a tendency toward variation 
in response to varied environmental conditions, occasion for erroneous 
identification has not been lacking. 
