104 
PLANTS INDIGENOUS TO 
\Zygophylleai. 
Plate YI. 1, flower; 2, petals and stamens; 3, a single petal; 4, back view of stamens; 5, pollen- 
grains; 6, style; 7, capsule, with one cell laid open; 8, transverse section of capsule; 9 and 10, seeds; 11, 
12 and 13, sections of the same: all figures variously magnified. 
Zyg-ophyllum Billardierii, Cand. Prodr. i. 705; Rcepera Billardierii, Adr. de Juss. in Mem. du 
Museum d'Hist. Natur. xii. 454; J. Hook. FI. Tasm. i. 60. 
Herbaceous, diffuse or procumbent, glabrous; stipules interpetiolar, often herbaceous; leaflets gemi¬ 
nate, fleshy, oblique-oblong- or linear-oblong or linear, entire, as long as or longer than the margined 
wingless petiole; terminal appendage of the leafstalk semilanceolate, acuminate; pedicels solitary! about as 
long as the petiole; sepals 4, persistent, lanceolate, acuminate, generally at least of half the length of the 
ovate-cuneate yellow spotless petals; stamens 8, about half as long as the corolla; filaments without 
appendages; anthers yellow; style rather short; stigma undivided; liypogynous disk divided into four 
semiorbicular lobes; ovary glabrous, with few ovules in each cell; capsule acute-quadrangular , semiovate- 
obpyramidate, wingless, drooping, truncate at the vertex; seeds solitary, rarely 2 in each cell, nearly three 
times shorter than the cavity; raphe adnate. 
On coast-rocks or drift-sand, dispersed from Port Phillip to the entrance of the Glenelg River; thence 
westward on many parts of the southern shores of Australia, extending, according to Mr. Oldfield, on the west 
coast at least as far north as the Murchison River; occurring also on the islands of Bass’s Straits; spread 
again inland over sandy desert-tracts from the Murray and its lower tributaries to Lake Torrens and Cooper’s 
Creek, being found on the latter locality by Mr. A. Gregoiy. 
A singularly variable plant. Root in younger plants cylindrical, branched, livid and apparently 
annual, although when on coast cliffs the plant becomes very robust and may' be perennial. Stems branched, 
when spreading over sand seldom more than 2 feet long and frequently shorter; when pendent from coast- 
rocks often several feet long, the plant thus assuming a most graceful appearance. Branches semiterete, 
margined with two decurrent lines, streaked at least in a dried state. Stipules 1-11 lines long, persistent,’ 
seldom membranous, roundish or deltoid or semilanceolate, with a minute or elongate sometimes linear- 
subulate always tender acumen. Petioles sometimes divided into several secondary' leafstalks, each of which 
is provided with a pair of leaflets. Leaflets of the coast-variety generally about 1 inch long and 3-5 lines 
broad, of the desert-variety often shorter, reduced occasionally to less than J inch length, about as long as 
the petiole or in various degrees shorter, generally opaque and blunt, sometimes, however, quite acute, rarely 
confluent with the petiole into a furcate leaf. StipeUar appendage more or less herbaceous or membranous, 
verging either into a more ovate or into a more subulate form, at times almost obliterated. Pedicels, accord¬ 
ing- to the manifold influences which the plant is capable to endure, varying from 1-10 fines in length, bent 
ownwarcl when fruit-bearing. Sepals 1-3 fines long, green, reflexed and more pointed in age, when the 
edges, as m other species, roll inward, occasionally less than half as long as the corolla. Petals bright- 
ye low, often retuse with a minute terminal apiculum, 3-6 fines long, rarely reduced to only 11 fine length. 
ilaments subulate, glabrous, yellow. Anthers nearly ovate, line long. Hypogynous "disk slightly 
papi ose-velvety at the margin. Style 1-U fine long, setaceous, not rarely twisted. Ovary-cells with 2 
or sometimes with several ovules. Stigmas not disintegrated. Capsules attaining a length of 1 inch, and 
measuring scarcely less at the vertex, often, however, considerably smaller, occasionally in meagre specimens 
w hen ripe only 2 fines long, very' slightly elevated at the vertex, more or less acute at the terminal angles, 
where not rarely a faint herbaceous appendage decurs. Endocarp scarious-parchmentous, separable from the 
closely net-veined sarcocarp, yellowish, inside polished. Seeds brown, considerably compressed, oblique- 
0 ong or midiate-orbicular, mostly opaque, 1-1J line long, affixed by means of a short funicle generally to 
above the middle of the internal angle of the cell, not so decidedly attenuated at the apex as any other 
species, the hilum being placed almost at the terminal extremity', and thus the raphe extends along the 
v 10 e inner side of the seed. Testa, when macerated, exuding a large mass of tough mucus, similar to that 
