STREPTACHNE r. brown and pheidochloa genus novum, etc. 21 
profunde sulcata. Lemmata pallida dorso lateribusque in majore parte 
breviter pubescentia, apicem versus glabra, nervis nonnullis saepe 
breviter setosa, eallo incluso 3*7-4*5 mm, longa; callus angustissimus 
pungens, breviter barbatus, 1-1*1 mm. longus; arista purpurea, basi 
admodum constricta, setacea, admodum applanata, 3*3-3*8 cm. longa. 
Paleae muticae lemmatibus subaequilongae, inter carinas elevatas 
planae, glabrae. Anther ae ovatae, minimae, 0*15-0*2 mm. longae. 
Lodiculae 0*5 mm. longae, tenuissimae. Caryopsis linearis, dorso convexa, 
2 mm. longa. 
Queensland. — Cook District : About 40 miles N.W. of Mungana, in 
Melaleuca forest on fine whitish sand, abundant, April 8th, 1938, Blake 
13732 (type) ; N. of Chillagoe, near Walsh R, in dwarf Mdaleuca 
forest on sand, ca. 1000 ft., April 2nd, 1938, Blake 13592. 
A delicate annual grass (plate II) with filiform culms, short 
setaceous leaves and long-exserted inflorescences of few, 2-flowered 
spikelets with long purple awns. Most culms bear a short floriferous 
branch from the penultimate node (topmost but one) ; the intemode 
above (penultimate internode) is much shorter than those immediately 
below, often the shortest on the culm, and this feature gives a peculiar 
facies to the plant. Occasionally a branch is also borne at the ante- 
penultimate node, and in this case the antepenultimate internode is 
rather shorter than the one immediately below, though much longer 
than the penultimate. The inflorescence, when consisting of up to 
4 spikelets, is a raceme, but when 5 or 6 spikelets are present the lower 
one or two branches bear a shortly pedicellate lateral spikelet, so that a 
depauperate panicle is the result. 
On account of the 2-flowered spikelets and the lemmas with a 
single terminal bristle-like awn this new genus is most closely allied to 
Eriachne R.Br., but the extraordinarily elongated upper glume (twice 
as long as the lower), the subterete florets deeply furrowed in front 
and with a pungent slender callus, the prominently inrolled (not merely 
incurved) margins of the lemma, the elevated keels of the palea and 
the peculiar very narrow grain are all quite distinctive features. The 
grain of Eriachne , so far as has been ascertained, is more or less obovate 
in outline and flat or nearly so on the anterior face. In E. meUcacea 
F.Muell. the grain appears to be constantly concave along the anterior 
face, but it is very different from that of Pheidochloa which has the 
margins incurved leaving a very deep furrow and giving a crescentic- 
reniform appearance in transverse section. The lodicules are extremely 
fine and delicate. The anthers are extraordinarily small and are always 
to be found tangled up with the stigmatic hairs in mature spikelets; 
the spikelets are very evidently cleistogamous. Small anthers associated 
with cleistogamy have been found in Eriachne triseta Nees, E. Armitii 
F.Muell. ex Benth., and E. stipavea F.Muell. var. hirsuta Hartley. 
Most species of this genus have relatively large anthers which are 
laterally exserted during anthesis ; they are usually 3 in number, though 
2 only in some of the small species such as E. ciliata R.Br. and E. fili- 
fonnis Hartley. Vegetatively Pheidochloa differs from Eriachne (except 
E. Dominii Hartley) in the very short penultimate internode of the 
culm and in that the leaf-blade is decidedly narrowed to the base from 
shortly above, but this latter character is not readily discernible unless 
the leaf-blade is artificially unrolled and flattened out. 
The position of the genus in the family is not clear, though Eriachne 
has usually been placed in the Aveneae. C. E. Hubbard (Hook Ic. PI. 
