AN ENCYCLOPADIA 
OF HORTICULTURE. 433 
Nematoid Worms—continued. 
membrane attached along one side of the hinder part of 
the body and the tail. Many other plants suffer through 
attacks of animals of the same genus; but the hurtful 
species are not fully known, and considerable doubt exists 
as to their true number as well as to their relationship to 
one another. During the past few years, their presence 
in a good many garden plants has been recorded in the 
“ Gardeners’ Chronicle,” and other horticultural journals. 
The diseases produced by them often seriously damage, 
if they do not even kill, the plants. Not less dangerous’ 
than the above are the Nematodes that gall the roots 
of plants. The swellings usually are to be seen on the 
root tips, though often they occur higher up the root. 
They vary greatly in size, from little larger than a pin’s 
head, on fine roots, to the size of a hazel-nut, or even 
larger. They are usually nearly round, or oval, though 
irregular forms are also common. The swelling is due to 
increase in the cellular tissue alone, the fibro-vascular 
tissue being hardly altered in any way. They are known 
to occur on a very large number of plants, both native 
and exotic, wild and cultivated, from grasses to Clover, 
and even on Coffee-trees, in South America. Among the 
most valuable plants injured by them must be specially 
mentioned the Sugar Beet, in its various forms, and 
also occasionally the Grape Vine. : 
In the galled roots of many plants a Nematode is met 
with, characterised by the fertile female becoming swollen, 
so as to resemble a lemon in form, with traces of the 
head and tail at the two ends. The female’s body be- 
comes united to the surrounding tissues, so as ultimately 
to look like a large cell merely, in which lie eggs, or 
young larve newly emerged from the eggs. This Ne- 
matode has received the name of Heterodera Schachtii. 
Attempts have been made to show that almost all root 
galls of Nematodes are the work of this species; but in 
Scotland the writer has never met with Heterodera in root- 
galls, but only with true species of Tylenchus. The 
animals, in autumn, pass from the food-plants, when 
these die and decay, into the surrounding soil, ready to 
make their way the following spring to the new crop of 
food-plants, should there be any such within their reach. 
Hence, the best mode of prevention consists in changing 
the crops on any piece of ground, so as to prevent suit- 
able food for the Nematodes being afforded during the 
ensuing season. On infested soil, therefore, plants liable 
to attack should be followed by others unsuitable as 
food for the Worms. It is well, also, to use only clean 
seed, from a crop in which the disease has not appeared ; 
and farmyard manure is somewhat dangerous, as liable 
to spread the Worms from diseased to healthy plants, 
either in the garden or the field. ; 
If any plants show signs of being severely attacked, 
they should be at once burnt, to prevent extension of 
the disease from them to others that are healthy. 
NEMATOPHYLLUM. Included under Temple- 
tonia (which see). . 
NEMATOSTIGMA, of Dietrich, A synonym of 
Libertia (which see). 
NEMATUS. A very large genus of Tenthredinida, 
or Sawflies, of much importance because of the harm 
done by the larva to various trees and shrubs, but 
especially to Willows, Gooseberries, and Currants. They 
are the type of a sub-family, Nematina, that has the 
- larva provided with fourteen sucker feet. In this sub- 
family it is distinguished from the other genera by- the 
form and arrangements of the nerves of the front wings, 
and of the cellules formed by them. The insects are 
never large, and they bear so great a likeness" to one 
another that it is most difficult to distinguish the 
species, since they are mostly smooth and shining, are 
seldom, if ever, punctured, and do not vary in pubes- 
cence. By their colour, the species may be divided 
Vol. II. 
Nematus— continued. 
into groups: (1) Abdomen wholly bick; (2) abdomen 
banded with red; (3) body black and yellow; (4) body 
wholly yellow, or slightly marked with black; (5) body 
green. These groups, however, grade into one another, 
Mr. Cameron, in his work on British Sawflies, says 
that there may be 400 species of this genus in Europe, 
and he describes 107 from Britain alone. The larva 
vary much in habits. Some are gregarious, while others 
are solitary; most feed exposed, but some roll up the 
edge of the leaves, to form a tube, in which they live; 
and others form pea or bean-shaped galls on the leaves 
of Willows. Indeed, few kinds of these latter plants are 
entirely free from their galls; while on some bushes 
almost every leaf is loaded with them. The larve, when 
full fed, generally burrow an inch or two into the soil, 
and there form cocoons. The pup are usually green, 
often with a mixture of orange. It is impossible here 
to enumerate all the trees and bushes that are attacked 
by the larve; but a few of the more important are 
described. Gooseberries are ravaged by N. Ribesii, 
N. appendiculatus, and N. consobrinus; N. abbreviatus 
feeds on Apples and Pears; several kinds feed on Alder, 
| others on Birch; very many are to be found on Willows 
of all species. Of the Willow Sawflies, the following 
are gall-makers: N. vesicator, in bean-shaped galls in 
the leaves; N. ischnocerus, in rather long galls, in 
pairs along the midribs of the leaves; N. baccarwm, 
N. salicis-cinereew, and N. bellus, in pea-shaped galls on 
the lower surface of the leaves of various Willows; 
N. herbacee, in similar galls on Salix herbacea; N. galli- 
cola, in the bean-shaped galls so plentiful in leaves of 
Saliz alba and other large Willows; and N. Bridgmanni, 
in similar galls from Sallows; N. Vacciniellus forms 
galls on Vaccinium Vitis-idea. For methods of checking 
the ravages of such larvæ as feed exposed, see Goose- 
berry and Currant Sawfly. z 
NEMESIA (an old Greek name employed by Dios- 
corides to denote an allied plant). ORD. Scrophularineæ. 
A genus comprising about a score species of very pretty, 
South African, greenhouse, slender, annual or perennial, 
sometimes suffruticose, herbs. Flowers racemose at the 
tips of the branches, or rarely solitary in the axils; 
pedicels ebracteolate; corolla yellow, white, violet, or 
yarious-coloured. Leaves opposite. The few species in 
cultivation are treated as hardy annuals. Propagated by 
seeds, sown in early spring, in any ordinary soil. The 
seedlings should be thinned out when large enough to 
handle. 
. eynanchifolia (Cynanchum-leaved).* jl. rich lilac-blue, in 
spe an clusters. 8 J. ovate-lanceolate, remotely toothed, 
Stems square. A. 12ft. to 2ft. 1879. A pretty species. (G. C. 
n. S., xii. 136.) 
„ floribunda (bundle-flowered).* H. white and yellow, fragrant, 
M. 22 J. at length petiolate; upper ones sessile. 
h. lft, A very charming plant. (B. R. 1838, mn en 
versico ious- coloured). A. blue, lilac, or yellow 
T paer — og J. at length petiolate, 
ovate ; upper ones few, remote, sessile, oblong-lanceolate or linear, 
entire or dentate. k. bin. to 12in. 
NEMIA. A synonym of Manulea (which see). 
NEMOPANTHES (from nema, a thread, and anthos, 
a flower; in allusion to the filiform peduncle). Mountain 
Holly. Syn. Nuttallia, of De Candolle. ORD. Ilicineæ. 
A monotypic genus, the species being a very glabrous, 
much-branched, hardy shrub, with ornamental berries. 
Tt thrives best, in cold damp soils, in somewhat shaded 
spots, and is most readily propagated by means of 
seeds. 
canadense ian small, polygamo-dicecions, on long 
"3 slender . solitary 5 sparingly clustered; 
etals four or five, oblong-linear, spreading, distinct. May. Jr. a 
Baht red drupe, with four or five bony nutlets. l. alternate, 
oblong, deciduous, entire or slightly toothed. A. ft. North 
America, 1802. pm. Ilex canadensis and Prinos integrifolius. 
A. F. B. ii. 503. 5 
§ e 3 K 
