Page:New species of grasses from South America.djvu/1

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Vol. 36, pp. 195–198
December 19, 1923

PROCEEDINGS
OF THE
BIOLOGICAL SOCIETY OF WASHINGTON



NEW SPECIES OF GRASSES FROM SOUTH AMERICA.

BY A. S. HITCHCOCK.


In a recent collection of grasses made by Macbride and Featherstone in Peru, the following new species were found. Parts of the types are in the U.S. National Herbarium. A new species collected by Lützelburg in Brazil is also included, the type in the U.S. National Herbarium.


Bromus villosissimus Hitchc. sp. nov.

A cespitose dwarf perennial with very villous lemmas. Culms glabrous or puberulent, 5 to 12 cm. tall; sheaths pubescent or glabrate; ligule a very short membrane; blades flat or more or less folded or involute, pubescent on both surfaces, 1 to 5 cm. long, 1 to 2 mm. wide; panicle ovoid, 1 to 2 cm. long, consisting of a few contiguous, short-pedicelled spikelets; spikelets mostly 3 to 5-flowered, tawny or tinged with purple, about 1 cm. long; glumes somewhat unequal, rather thin, sparsely villous, acute, 3-nerved, the first 1 cm. long, the second broader and a little longer; lemmas densely villous with spreading or ascending hairs 2 to 3 mm. long, 7-nerved, about 8 mm. long, the apex 2-lobed, the teeth broad and short, the midnerve extending into a scabrous awn 1 to 2 mm. long; palea acute, a little shorter than the lemma, villous-ciliate on the keels.

Type in the herbarium of the Field Museum of Natural History, No. 517,382, collected in loose soil of alpine basin slopes, at about 4700 meters, Casapalca, Peru, May 21, 1922, by Macbride and Featherstone (No. 854).

The only other specimen seen was collected between Casa Caucha and Culea, Peru, by the Wilkes U.S. Exploring Expedition (U.S. Nat. Herb. 1,009,615).


Lamprothyrsus peruvianus Hitchc. sp. nov.

Plant perennial; culms erect, stout, glabrous, a meter or more in height; sheaths glabrous, papery, the basal ones not seen, the cauline apparently 3, the uppermost inclosing the base of the panicle, all separating from the culm along the upper part and inrolled, glabrous on both margins and more or less hyaline; ligule a dense row of hairs about 2 mm. long; blades (only the 3 cauline seen) loosely involute, narrower than the sheath at

34—Proc. Biol. Soc. Wash., Vol. 36, 1923.
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