158 GRAMINEAE. [ Deyeuxia. 
bristle. Glumes 3; 2 outer equal or subequal, persistent, empty, keeled, 
acute, not awned, usually l-nerved ; 3rd or flowering glume shorter than 
the empty glumes or equalling them, thin and hyaline or rigidly mem- 
branous or almost coriaceous, 5-nerved, entire or 2—4-dentate, callus at 
the base silky ; awn generally present, straight or twisted, inserted above 
or below the middle of the glume. Palea more than half as long as the 
flowering glume or almost equalling it, thin, 2-nerved or 2-keeled. Sta- 
mens 3. Styles distinct, short ; stigmas plumose. Grain oblong or obovoid, 
enclosed within the flowering glume and palea. 
Species over 100, widely dispersed throughout the temperate regions of both 
hemispheres, particularly abundant in Andine South America. It is not at all easy 
to separate Deyeuxia from the allied genera Agrostis and Calamagrostis, and of late 
many authors, including Hackel, have placed the majority of the species under the 
latter genus. But it has always appeared to me that for taxonomic purposes it is 
desirable to have a genus intercalated between the typical species of Agrostis on the 
one side and Calamagrostis on the other. In the first edition of this work I therefore 
followed the arrangement proposed in Hooker’s “Flora of British India” (vol. vii, 
p. 253), where Agrostis is limited to species in which the rhachilla is not produced at 
the back of the flower, and in which the callus of the flowering glume is naked or 
nearly. so, Calamagrostis containing those in which there is also no prolongation of the 
rhachilla, but which have the callus villous with long hairs, while in Deyeuxia the 
species have both an elongated rhachilla and hairy callus. Further study has con- 
vinced me that this course is much to be preferred, particularly as there are no genuine 
species of Calamagrostis in New Zealand as originally limited. As defined above, 
there are 7 New Zealand species of the genus, 3 of which extend to Australia and 
Tasmania, the remaining 4 being endemic. 
* Flowering glume 4-4 shorter than the empty glumes, thin and hyaline. Panicle 
very broad and lax; branches long, spreading, capillary. 
Spikelets j4,-}in. Flowering glume silky, truncate, minutely 
4-denticulate ; awn from the middle of the back .. ye wh. WD, Bereter’é: 
Spikelets ;1,-4, in. Flowering glume quite glabrous. Awnshort 2. D. glabra. 
Spikelets 2-}in. Flowering glume silky at the base only, 2 
lateral nerves produced into short awns, dorsal awn from 
below the middle of the back .. bs ‘4 .. 3 D. Billardiert. 
** Flowering glume not much shorter than the empty glumes, rigidly mem- 
branous. Panicle narrow, contracted. 
Slender, 4-12in. Leaves filiform. Panicle 1-24in. Spikelets 
4in. long; callus-hairs very long £9 or ies 
Slender, 9-36in. Leaves narrow, involute. Panicle 2-5 in. 
Spikelets 4-tin.; awn from below the middle, exserted ; 
callus-hairs short. Rhachilla obviously produced .. .. 5. D. avenordes, 
Tall, slender, 2-4 ft. Leaves flat, }-+ in. broad. Panicle 4-6 in. 
Spikelets +-+in.; awn short, almost terminal. Rhachilla 
obviously produced . . nt = We 
Tall, stout or slender, 1-3 ft. Leaves flat or involute. Panicle 
2-6in. Spikelets }in.; flowering glume 4-cuspidate; awn 
from near the base. Rhachilla not produced or very obscurely 
4. D. setifolia. | 
6. D. Youngti. 
BO tt ot Arai 5 ae - .. 7. D. quadriseta. 
“P. $25 Sommas (feck) Hook-§. 1617.28. 
_ 1. D. Forsteri Kunth Rev. Gram. i (1829) 77.—Annual or rarely peren- 
nial, very variable in size and habit. Culms tufted, erect or decumbent 
at the base, slender, smooth, 2-4-noded, 6-24in. high. Leaves shorter 
than the culms, very narrow and involute or broader and flat, qs in. 
diam., almost glabrous or scaberulous on the margins and principal veins ; 
sheaths smooth, grooved, the uppermost usually long; ligules long, narrow, 
membranous. Panicle 3-12 in. long, usually very lax and spreading when 
. mature, but contracted in the young state; branches in distant whorls 
or clusters, the lowermost 2-6 in. long or more, repeatedly trichotomously 
divided, finely capillary, scabrid ; pedicels very slender. Spikelets numerous, 
