248 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
is typically smaller, more slender and stiffer than P. isugetorum, and the culms are 
densely crisp-puberulent with little of the pilose character of the latter. Occasional 
specimens, like Bissell 5596, Chase 3822, and Graves 10, are larger, laxer plants with 
appressed-pilose culms and are referred to P. columbianum because the spikelets are 
not over 1.6 mm. long. 
DISTRIBUTION. 
Sandy woods or open ground, Maine to Virginia.¢ 
Marne: North Berwick, Parlin 1196; York Harbor, Bicknell in 1896. 
New Hamesuire: Laconia, Carter in 1902 (Hitchcock Herb.). 
Massacuusetts: Wellesley, Smith 738; Framingham, Smith 742, 744, 
Connecticut: Griswold, Graves 10; 
Waterford, Graves 83, 84; 
Southington, Andrews in 1902, 
Bissell 5596. 
New York: Van Cortlandt Park, 
Bicknell in 1891; Rockville 
Center, Bicknell in 1903 and 
1906; Cedarhurst, Bicknell in 
1903; Hempstead, Bicknell in 
1903; Jamaica, Bicknell in 
1905. 
New Jersey: Tuckerton, Chase Fig. 268.—Distribution of P, columbianum. 
3606, 3613; Atsion, Chase 3533, 
3539; Wildwood, Chase 3519; Toms River, Clute 175; Mount Arlington, 
Mackenzie 1399; Lakehurst, Mackenzie 2068; Chadwick, Mackenzie 2404; South 
Amboy, Mackenzie 2247; Sussex County, Mackenzie 2105, 
PENNSYLVANIA: Stroudsburg, Porter in 1898. 
MARYLAND: Patuxent River, [/itchcock 1632; Chesapeake Junction, Iitchcock 
2407, 2413; Beltsville, Chase 3794, 3832; West Chevy Chase, Chase 5427, 
District oF CoLtumBIA: Chase 5429, 5430, Hitcheock 2418, Scribner in 1894, 
Williams in 1896. 
Vireria: Norfolk, Vasey in 1884 (Gray Herb.). 
147a. Panicum columbianum thinium Hitchc. & Chase. 
Panicum unciphyllum thinium Hitche. & Chase, Rhodora 8: 209. 1906.  “‘Type 
Chase 3577 in National Herbarium. In mats, sandy, open ground, Tom’s River, N. J., 
July 28, 1906; collected by Agnes Chase’’. The type consists of a tuft of many autum- 
nal culms 12 to 20 cm. high, the spikelets 1.3 mm. long. 
Panicum columbianum thinium Hitche. & Chase in 
Robinson, Rhodora 10: 64. 1908. Based on P. unci- 
phyllum thinium Hitche. & Chase. 
DESCRIPTION. 
Vernal culms shorter and more slender than in P. colum- 
bianum, not over 30 cm. high,usually about 20 cm. high, 
densely tufted, the appressed pubescence longer, stiffer, 
and arising from minute papill:e; sheaths sparsely ascending pilose; blades rarely over 
3cm., long, sparsely pilose with long hairs on the upper surface at least near the margin 
Fia. 269.—P. columbianum thini- 
um. From type specimen. 
a The extended range given with the original description was based on misidentifi- 
cation of various small specimens of P. lindheimeri, as shown by such specimens 
labeled by Scribner ‘‘ Panicum columbianum” in the National Herbarium and in 
Hitchcock’s herbarium. 
