318 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
upper surface; panicles 6 to 12 cm. long, as wide or wider, the main axis and the 
flexuous spreading or ascending branches puberulent; spikelets 4 to 4.5 mm. long, 
2 to 2.2 mm. wide, oblong-obovate, less turgid than in P. latifolium, papillose- 
pubescent; first glume one-third to two-fifths the length of the spikelet, pointed; 
second glume slightly shorter than the fruit and sterile lemma at maturity; fruit 3.2 
to 3.5 mm. long, 1.5 to 1.6 mm. wide, elliptic, minutely pubescent, and usually black 
at the tip. 
Autumnal form as in P. latifolium, rather more freely branching, sometimes top- 
heavy reclining; spikelets more turgid than those of the primary panicles. 
As in P. commutatum, what appear to be simple, very leafy, autumnal culms are 
commonly formed by the replacing of the fallen primary summit by the uppermost 
branch. These culms are often 
recurved, the blades all turned into 
the plane of the branch, or even all 
to one side, from a twisting of the 
internodes, and more or less unsym- 
metrically expanded in the middle, 
the whole producing a very different 
aspect from that of the vernal form. 
This species is closely related to 
P. latifolium and is often difficult 
to distinguish from pubescent speci- 
mens of that species. 
The form distinguished by Vasey 
as P. latifolium australe can not be 
satisfactorily separated. The longer 
Fig. 357.—P. boscii. From type specimen. spikelets and blades narrowed to the 
base, or rather expanded in the 
middle, are not correlated. Specimens with large spikelets are mostly of southern 
range, but those with blades strongly tapering to the base occur throughout, Andrews 
40, Connecticut, being a pronounced case. The following specimens represent this 
variation: Chase 4491, Combs 334, 337, 399, 683, Commons 361, Hall 828, Harper 1812, 
Mohr in 1888, Nash 2329. In most of the Alabama and Florida specimens the longer 
spikelets and tapering blades are correlated and might be given subspecific rank but 
for the more numerous intermediate specimens. The larger spikelets and tapering 
blades also occur in P. boscii molle. 
The following specimens are intermediate in character between P. boscti and P. 
boscti molle, having blades more or less downy, or glabrous and downy blades on the 
same plant: Bush 303, 310, 3348, Chase 4501, Harper 1366, Tracy 3 in 1888. 
DISTRIBUTION. 
Woods, Massachusetts to Oklahoma, south to northern Florida and Texas. 
MassacuusEtts: Monson, /erb. Western High School of Washington (Biltmore 
Herb.). 
Connecticut: Southington, Andrews 40, Bissell 5552; Ledyard, Graves in 1897. 
New Jersey: Byram Station, Fisher in 1897; Milburn, Mackenzie 2144. 
PENNSYLVANIA: Lancaster County, //eller 4771; Upper Darby, Smith 154. 
Onto: Painesville, Werner in 1886; Cincinnati, Lloyd 3597. 
Inpiana: Clarke County, Deam 5386, 6586. 
Inurvors: Marshall County, V. H. Chase 1489; Jackson County, French in 1905; 
Tunnel Hill, Ridgway in 1902; Wabash County, Schneck in 1896. 
Missourt: Allenton, Kellogg 15; Pleasant Grove, Bush 303, 310, 323; Doniphan, 
Bush 276; Swan, Bush 26, 4534; Monteer, Bush 4652, 4908. 
