OF HORTICULTURE. 25 
Thelebolus—continued. 
is about }in. in diameter, and is surmounted above by a 
prominent, round mouth. In these bodies the spores are 
formed, and when they are ripe for being scattered they 
are pushed, or thrown, from the mouth in a mass which 
resembles a small nipple in form; hence the name of 
the genus. When the spores have all been ejected, the 
top of the Fungus sinks in, so that it resembles a cup. 
This plant is not of any practical importance to gardeners, 
though the yellow patches formed by it render it very 
conspicuous. 
THELEPHORA (from thele, a nipple, and phero, to 
bear; in allusion to nipple-like growths on the surface of- 
the hymenium in some of the species). A genus of Fungi, 
most of which grow on the ground in woods. A few, 
however, are found on tree-trunks or stumps, and at 
times do mischief to the wood, burrowing between and 
through the annual rings of growth. Thelephora belongs 
to the group of Mushrooms in regard to the structure of 
the hymenium, or part on which the spores are formed, 
and in four spores being formed from each large cell of 
the hymenium (see Mushrooms); but it differs from 
the true Mushrooms in having the hymenium smooth, or 
bearing mere ridges or warty growths, instead of being 
spread over gills; and the texture is firm and dry— 
indeed, almost leathery. 
- The reproductive organs of T. laciniata appear on the 
diseased trunks in the form of horizontal, semicircular 
plates, attached by the middle to the-bark or wood; a 
number of such plates uniting, and overlapping one 
another, to form a mass 4in. or more across. They are 
covered above with a coat of fibrous or scaly hairs, 
prolonged round the margins; and each bears the 
downy, warty hymenium on its lower surface. The whole 
mass is dull rusty-brown. This Fungus is usually found 
among the leaves and other plant-remains in the soil in 
woods; but it often grows closely around the stems or 
branches of young trees, and thereby kills small or 
weakly plants, although it is not a true parasite. It is 
AN ENCYCLOPADIA 
Thelephora—continued. 
is yellowish. Where this Fungus gains an entrance into 
an Oak-trunk, the wood becomes brown, at first on one 
side, then gradually all round, in concentric layers. In 
the brown wood there next appear snow-white or yellowish, 
longitudinal streaks, which, in cross-sections of the trunk, 
show themselves in the form of small spots. Where air 
gains free access, through cracks, &c., the wood may 
become uniformly yellowish, the middle layer of the 
wall between the cells is dissolved out, and the tenacity 
of the wood is destroyed by the cells thus becoming 
separated. Fortunately, Stereum hirsutum does not often 
attack healthy trees. As is the case with almost all 
internal parasites, comparatively little can be done to cure 
the evil in a tree; though timely removal of diseased 
branches may prevent the mycelium from reaching the 
trunk. But, except in the case of choice specimens, 
the wise course is to remove and burn, without delay, 
such trees as show signs of being occupied by the Fungi, 
in order to prevent the latter from spreading to healthy 
plants. 
THELESPERMA (from thele, a nipple, and sperma, 
seed; alluding to the nipple-like protuberances on the 
achenes). Syn. Cosmidinm. Orn. Composite. A small — 
genus (four or five species) of stove or greenhouse, 
glabrous herbs or sub-shrubs; one is found in extra- — 
tropical South America, and the rest are Mexican. 
Flower-heads mediocre, heterogamous, on long peduncles; 
involucre duplex; ray florets, when present, yellow; disk- 
often purplish; achenes glabrous, smooth or tubercled. 
Leaves opposite, or the upper ones alternate, linear, 
often filiform, once or twice pinnatipartite or the upper- — 
most ones undivided. The species are probably not now 
in cultivation in this country. 
THELIGONUM. See Thelygonum. 
THELYGONUM (an old Greek name, from thely- | 
gonos, begetting girls; it was said by Pliny to give the 
power of producing female offspring). Sometimes spelt 
Thelig Syn. Cynocrambe. Orv. Urticaceew. A 
unsafe to form nurseries for seedlings where T, laciniata 
abounds, though this species is seldom dangerous to 
older trees. $ ; 
Dr. Hartig, the well-known German writer on the 
diseases of trees, has described (in the “Lehrbuch der 
Baumkrankheiten”) a disease of Oak-trunks, widely met 
with in Germany, which he attributes to a Fungus, 
named by him T, Perdiæ. The specific name is the 
Latin word for a partridge, and alludes to the fact that 
the wood in which it grows often resembles in its 
mottlings the plumage of a partridge. The diseased wood 
turns to a deep red-brown, with numerous white spots of 
mycelium. These spots soon become closed cavities, 
which are lined with the pale threads of the Fungus. — 
The wood rots, turning dark brown, and the cell walls 
and cell contents decay. The reproductive organs, 
which are the most readily recognised parts of the 
Fungus, are semicircular plates from j;in. to din. 
across, and of a brown-yellow colour; and they grow 
_ on the surface of dead: branches, or in hollow spaces 
in the trunks. These plates continue to increase in 
size year after year. Though so frequent in Germany, 
T. Perdix does not appear to have been recorded as 
British. 
Another Fungus formerly known as T. hirsuta, but 
now named Sterewm hirsutum, is very frequent in Britain, 
on stumps and dead wood of many species of trees. It — 
also is regarded by Dr. Hartig as at times very hurtful 
to Oak-wood. In general appearance it is much like a 
true Thelephora, but differs in having between the 
hymenium and its support (pileus) a fibrous layer that 
is not present in Thelephora. The reproductive bodies of 
Stereum hirsutum are somewhat like those of T. laciniata 
in general form; but they are usually pale, and are 
covered above with grey or pale down, and the hymenium 
Vol. IV, : 
eap; alluding to the hood-shaped column). 
- longifolia (long-leaved). fl. blue, lilac, or pink, rather large, 
ye in a le te wing ita a g behind and e 
monotypic genus. The species, T. Cynocrambe (Dog’s 
Cabbage), is a hardy, slightly fleshy, procumbent, annual 
herb, broadly dispersed over the Mediterranean region. 
It is occasionally cultivated as a potherb, but has no 
value from a horticultural standpoint. ete 
THELYMITRA (from thelys, a woman, and mitra, a 
Woman’s-cap 
Orchid. Including Macdonaldia. Orp. Orchidee. A 
genus comprising about twenty species of greenhouse, 
terrestrial Orchids, with ovoid tubers; one is broadly | 
dispersed through Australia, New Zealand, New Caledonia, 
and the Malayan Archipelago, three or four are indigenous 
to New Zealand, and the rest are all Australian. Flowers 
blue, purple, red, or yellow, occasionally white, usually 
several in a terminal raceme ; sepals, petals, and lip, all 
nearly equal and spreading; column rather short, erect, 
broadly winged; pollen masses granular; bracts shorter 
than the flowers. Leaves linear, lanceolate, or rarely — 
ovate, sometimes rather thick, but not terete. Stems 
simple, one-leaved. A selection of the introduced species 
is given below. All of them are Australian. For culture, 
see Bletia. , 
carnea (fleshy). . pink, one to three; sepals and petals 
Saeco de 5 Cheam, usually about four lines long. 
May. J. narrow-linear. Stem slender, often flexuous, less than 
bin. to nearly 12in. high. 1820. 
T, Forsteri (Forster's). A synonym of T. longifolia. 
T, graminea (grass-like). A synonym of T. longifolia. 
' ixioides (Ixia-like). /l. blue, pedicellate, usually forming a 
a oe eke 6in. Tak sepals, petals, and lip, elliptic-oblong, 
nine to ten lines I May. l. long-linear or linear-lanceolate, 
flat or channelled, with one or two shorter ones. Stem usnally 
- above 1ft. high, 1810. (S. E. B. 29.) 
E 
