EXPLANATION OF THE PLATES. 



Genera of Graminese, or Grasses. 



TAB. I. 



LEERSIA. Panicle of L. oryzoides, reduced in size (1); a branchlet of the same with it* 

 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 hypogynoua 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 base of the albumen. 



ALOPECURU5. 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 palea> 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 palese 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) i with an enlarged open spikelet of the same : also (3) 

 the rough pedicel aod 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) 5 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 th 

 palea?, the single stamen, and the pistil (2). 



MUHLENBERGIA. A magnified closed spikelet of M. gylvatica (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). 



