Box 16, Folder 6: Grasses of the U.S. Illustrations

Leersia.-Panicle of L. oryzoides, reduced in size (1); a branchlet of the same with its spikelets, of the natural size (2); and an open spikelet in flower, enlarged (3).

Zizania.- A staminate (1) and a pistillate (2) flower or spikelet of Z. aquatica; a magnified pistil with a pair of squamulae or hypogynous scales (3); a grain (4); and a magnified longitudinal section of the lower part of the same, showing the embryo at the outside of the albumen.

Alopecurus.-Part of a plant of A. geniculatus, in flower (1); a few spikelets from the spike-like inflorescence, moderately magnified (2); an open spikelet in flower, more magnified (3), and the single lower palea detached (4).

Phleum.-One spikelet of P. pratense, having the flower with its paleae raised above the glumes, magnified.

Crypsis.-Inflorescence (1) of C. schoenoides (see Addenda, p. xcix); a separate enlarged spikelet (2); and the same open, in flower (3).

Vilfa.-An enlarged spikelet of V. vaginaeflora (1); and the same displayed (2).

Sporobolus.-A spikelet of S. cryptandrus, magnified (1); the same with the flower open, the paleae raised above the glumes (2); and the fruit (3);, more magnified, showing the seed loose in the pericarp (utricle).

Agrostis.-Panicle of A. vulgaris (1); with an enlarged open spikelet of the same: also (3) the rough pedicel and glumes of A. scabra, with the flower separated, the latter having no upper palea.

Tab II.

Polypogon.-Spike-like contracted panicle of P. Monspeliensis (1); an enlarged detached spikelet, showing the long awns to the glumes (2); the same open in flower (3); and a separate flower without the glumes (4).

Cinna.-A magnified spikelet of C. arundinacea (1); and the same, open, displaying the paleae, the single stamen, and the pistil (2).

Muhlenbergia.-A magnified closed spikelet of M. sylvatica (1); the same with the open flower raised out of the glumes (2). A magnified spikelet of M. diffusa (3); its minute and unequal glumes more magnified (4); and an open spikelet of the same (5).

Bouteloua.-A portion of the compound spike, of the natural size (1); and a spikelet displayed and magnified (2), the flowers raised out of the glumes.

Gymnopogon.-Inflorescence of G. racemosus, reduced in size (1); and a magnified spikelet with the parts displayed (2).

Cynodon.-Inflorescence, of digitate spikes (1); a spikelet magnified and displayed, showing a perfect flower and a rudiment (2).

Dactyloctenium.-Inflorescence of D. Egyptiacum, of digitate spikes (1); one of the spikelets magnified (2); the fruit magnified (3), showing the seed loose in the thin pericarp (utricle); and (4) the wrinkled seed more magnified.

Eleusine.-One of the spikes from the digitate inflorescence of E. Indica (1); a magnified spikelet (2); the same with the flowers more displayed (3); a flower from the last showing its parts (4); the fruit magnified, showing the seed loose in the utricle (5); and the wrinkled seed detached (6).

Leptochloa.-Small portion of the inflorescence of L. fascicularis (1); one of its spikelets displayed and magnified (2); an open flower of the same (3).

Tab IV.

Tricuspis.-Magnified spikelet of T. seslerioides (1); the same displayed and the lowest flower open (2); back view of the lower paleae spread out (3).

Dupontia, or, as it should be, Graphephorum (see Addenda, p.c).-A magnified spikelet of Dupontia Cooleyi or Graphephorum melicoides, displayed (1), a part of the hairy rhachis and one flower of the same (2).

Diarrhena.-A spikelet of D. Americana, enlarged (1); the grain and paleae (2).

Dactylis.-A spikelet of D. glomerata magnified and displayed.

Koeleria.-A magnified spikelet of K. cristata, expanded, showing the glumes, the three flowers, and a rudiment (1); lower half of a lower palea, partly spread open (2); it is much more folded and keeled in its natural condition.

Eatonia.-A magnified spikelet of E. obtusata, expanded, showing the glumes, the two flowers, and a rudiment.

733 EXPLANATION OF THE PLATES.

MELICA.- A magnified spikelet of M. mutica, expanded, showing the glumes, two perfect flowers, and an abortive one. GYCERIA.- A magnified spikelet of G. nervata (1); a separate flower with one joint of the rhachis (2); and (3) the lower half of a lower palea, showing its form (rounded on the back, not keeled.) BRIZOPYRUM.- A pistillate spikelet of B. spicatum, enlarged (1); a flower from the same (2); and a flower from a staminate spikelet (3). POA.- Panicle of P. compressa, reduced in size (1); a magnified spikelet (2); a separate flower more magnified (3); a lower palea cut across and somewhat outspread (4). ERAGROSTIS.- A spikelet of E. pilosa, enlarged (1); the same, from which the glumes and all of six lower flowers except the upper palea have fallen away (2); a magnified flower, open (3); the lower palea of the same outspread (4). BRIZA.- A spikelet of B. media, enlarged (1); a separate flower (2). FESTUCA.- A spikelet of F. elatio. enlarged (1); a separate flower (2); lower part of a lower palea, outspread (3). BROMUS.- A spikelet of B. secalinus, of Chess (1); a separate flower, enlarged (2).

TAB. V.

UNIOLA.- A spikelet of U. latifolia of about the natural size (1); a flower, enlarged (2); empty lower palea of the lowest (sterile) flower (3). PHRAGMITES.- A spikelet of P. communis, enlarged (1); one of the perfect flowers, enlarged (2); and the lowest flower (3), which has stamens only. ARUNDINARIA.- A spikelet of A. macrosperma (1); a separate flower, magnified (2). LEPTURUS.- Portion of the spike of L. paniculatus, enlarged (1); a flower magnified (2). LOLIUM.- Portion of the spike of L. temulentum (1); a separate flower, magnified (2). TRITICUM.- Portion of the spike of T. repens, or Couch-Grass, of about the natural size (1); a flower magnified (2). HORDEUM.- The three one-flowered spikelets from one joint of the spike of H. jubatum, with their awn-like glumes, the lateral flowers abortive and neutral, the middle one alone perfect (1); this perfect flower (with an awn-like rudiment) open and enlarged (2). ELYMUS.- The two spikelets of one joint of the spike of E. Virginicus, about the natural size (1); the glumes and the flowers of one spikelet, enlarged and displayed (2); and an open flower, more magnified (3). GYMNOSTICHUM.- A spikelet of G. Hystrix (1), and an expanded flower, magnified (2).

TAB. VI.

AIRA.- Panicle of A. flexuosa (1); a spikelet, magnified, the parts displayed (2); and one of the flowers detached and open (3). DANTHONIA.- Panicle of D. spicata (1); a spikelet enlarged (2); and a separate flower from the same (3). TRISETUM.- A spikelet of T. subspicatum, var. molle, expanded and magnified (1); and a separate open flower (2). AVENA.- A spikelet of A. striata displayed and magnified (1); and a separate flower (2).

734. Explanation of the Plates.

Arrenatherum.-A spikelet of A. avenaceum displayed and magnified: 1, the glumes; 2, the flowers, the lower one staminate only, the next perfect, and the third a rudiment.

Holcus.-A spikelet of H. lanatus magnified (1); the same displayed to show the two flowers, the lower one perfect and awnless, the upper staminate and awned (2).

Tab VII.

Hierochloa.-A spikelet of H. borealis, enlarged (1); the same displayed, the flowers separated from the glumes, the two lateral ones with three stamens and no pistil; the middle or terminal one with a pistil and only two stamens (2).

Anthoxanthum.-The spike-like inflorescence of A. odoratum (1); a spikelet magnified (2); another with the parts displayed, the flowers raised from the glumes, the lateral ones neutral, each of a single and awned palea, the middle one perfect and diandrous (3).

Phalaris.-A spikelet of P. arundinacea enlarged (1); the glumes and the perfect flower with a hairy rudiment on each side of it (2).

Milium.-Portion of the panicle of M. effusum (1); a closed spikelet magnified (2); and the same displayed (3).

Amphicarpum.-A spikelet from the panicle of A. Purshii, magnified (1); the same with the parts displayed (2); and a radical (fertile) spikelet, enlarged (3).

Paspalum.-Inflorescenc eof P. laeve (1); a closed spikelet, enlarged (2); the same with the parts displayed (3).

Panicum.-Part of a spike of P. (Digitaria) sanguinale (1); one of its spikelets magnified (2); the same with the parts displayed (3); in this the lower flower is neutral and of a single palea. A spikelet of P. capillare, magnified (4); and the same displayed (5); the lower flower of a single palea. A spikelet of P. clandestinum, magnified (6), and the same displayed (7); the lower flower neutral, of two paleae. A spikelet of P. virgatum, magnified (8); the same displayed (9); the lower flower of two paleae and staminate.

Setaria.-A magnified spikelet of S. glauca, with the accompanying cluster of bristles (1); the spikelet displayed, showing the neutral lower flower of two paleae and the perfect flower (2).

Tab VIII.

Cenchrus.-A spiny involucre of C. tribuloides, in flower, enlarged (1); the longitudinal section of the same (2); a spikelet detached and displayed (3): the stigmas should belong to the right-hand or upper flower; the land-hand, or lower flower is only staminate.

Tripsacum.-Piece of the spike (of the natural size), pistillate below, staminate above (1); a longitudinal section of one of the pistillate spikelets (2); a pistillate spikelet with its parts displayed (3); a staminate (2-flowered) spikelet, with its parts displayed (4).

Erianthus.-Part of the hairy inflorescence with two spikelets of E. alopecuroides, enlarged (1); one of the spikelets displayed (2).

Andropogon.-Small portion of the spike of A. furcatus, enlarged with one fertile and awned spikelet, and one staminate and awnless spikelet (1); the fertile spikelet (2), and the staminate spikelet (3) displayed.

Sorghum.-A fertile spikelet of S. nutans, enlarged, with a sterile pedicel on each side (1); the spikelet displayed (2).