AN ENCYCLOPADIA OF Н ORTICULTURE. 475 
Dieffenbachia—continued. Diervilla—continued. 
D. triumphans (triumphant), Z, dark green, covered with large, | D. trifida (trifid), Л. yellow. Summer. l on short tioles, 
irregular, angular, yellowish-green blotches, somewhat spread- 
ing, ovate-lanceolate, attenuately acuminate, about lft. long, and 
4in. to 5in. wide. Columbia. A very ornamental species. 
у ii (velvety). l satiny-green ; petioles white. Columbia, 
D. Verschaffeltii (Verschaffelt’s). 
a quiniana. 
D. vittata (striped) l. greyish-green, with two feathery white 
bands. ‘Tolima. 
D. Wallisii (Wallis's).* Z, ovate-lanceolate, of a rich dark green, 
marked along the midrib with broad feathery bands of a light 
grey, ornamented with irregular blotches of the same colour to- 
wards the margin. Columbia, 1870. (I. H. 1870, 11.) 
D. Weirii (Weirs) 1. bright green, thickly blotched and spotted 
with pale yellow. Brazil, 1866. А fine species, of dwarf habit. 
DIELYTRA. This name, by an erroneous conjecture, 
. was changed from Diclytra, in the first instance acci- 
dentally printed for Dicentra (which see). 
DIERAMA. See Sparaxis pendula and S. pul- 
cherrima. 
DIERVILLA (named in honour of M. Dierville, a 
French surgeon) Syn. Weigelia. ORD. Caprifoliacec. 
A genus of very handsome hardy 7 
= shrubs. Flowers white, purple, 
. pink, or yellow, in axillary and 
_ terminal clusters; corolla fun- 
. nel-shaped or eampanulate; tube 
regular. Leaves opposite, ses- 
sile, or petiolate, serrated. These 
elegant shrubs are of very easy 
culture in common garden soil, 
if the situation is a rather moist 
and shaded one. Propagation 
may be readily effected by cut- 
tings, made in spring or antumn, 
or by the freely-produced suckers. 
The gracefully spreading form of 
ably well adapted for shrubberies ; 
and D. grandiflora, in particular, 
be very successfully grown 
a wall-plant. 
amabilis (lovely. A synonym 
f D. grandiflora. 
A synonym of D. Bara- 
M 
many-flowered). f., 
; and Van Ир i, white and _ 
very showy (F. d. S. 1447); 
ly variegated leaves (F. d. S. 
| Ета. 666. DIERVILLA 
(garden) fl. red or ROSEA. 
"mte ; corolla tube slender, slightly 
hairy outside, glabrous within ; limb regular, with spreading ovate 
lobes, z, stalked, ovate, acuminate, crenate, or crenate-serrulate, 
tly hairy. A. 4ft. to 5%. Japan. (S. Z. F. J. 29.) 
Cet etn ome rie i 
"nu r : ез n near: e, 
ovate-lanceolate, finely Feticulated, hairy on the nerves. Siberia. 
ovate, acuminated, serrated, and, as well as the petioles, Е brous, 
Root creeping. А. Әй. to 4ft. North America, 1739, SYN 
D. canadensis. 
DIFFUSE. 
DIGGING. For pulverisation and mixing-in of 
manures, Digging is best performed (says Loudon) in dry Y 
weather; but, for the purpose of aération, a degree of 
moisture and tenacity in the soil is more favourable. In 
Digging, a uniform depth should be preserved throughout, 
the full length of the spade being inserted nearly vertically, 
and the spit turned over, so that what was before under- 
neath may now be exposed to the air. An open trench, 
the length of the ground to be dug, should first be made, : 
and the soil thus removed transferred to the place where Р 
it is intended to finish. In order to leave the surface, 
when completed, evenly disposed, the trench must be kept 
tolerably straight, and of about an even width. Ground 
that has been occupied by garden crops in summer, is best 
thoroughly dug in the autumn, and manure added. It 
should not be broken by the spade, but left rough for 
full exposure to the frost, and for the consequent aération 
in winter. The following spring, such soil will be found 
to work well, and may be prepared, by levelling down, for 
any desired crop. The strength of the manure will also 
have become incorporated with the soil underneath—a 
condition that cannot be obtained by adding it at planting js 
time. The width of ground taken as а spit must not a 
exceed about Iin. in heavy soils, or the bottom will be * 
left undisturbed. Digging is best performed when the 
soil is somewhat dry, and should never be practised when 
it is frozen or covered with snow. Light soils, or those 
resting on а gravelly bottom, may be worked at many 
Scattered; widely spread. 
2 
. times when it would be very unwise to tread on those of 
. & clayey nature. The workman, 
when Digging, should 
stand nearly erect, insert the spade vertically, to secure 
the removal of soil to the full depth, and turn the spit 
from the direction in which he is standing. If a com- 
petent man, he will be able to reverse the position of his 
cr the spade, and proceed either way with equal 
Double-digging is performed by having a trench or : 
double width, removing a spit of the earth on the top, D 
then Digging underneath, and alowing that portion to nor 
remain. Another width is then marked out, the top si : 
from this placed on the other, and each portion treated 
successively in a similar manner. This method is often 
adopted where sub-soils are poor, so that the depth of 
two spits may be reached, without introducing the in- 
ferior soil to the surface. : 
sions. x : 
D. am ous)* jt yellowish, retict with brown, 
large, 2in. long; Doo M about equal in length to the 
flowers, July, August. UR A toothed, suis, 
Tho bay ee oe le оға and D. ochroleuca. (B. В. 
i^ hairy Syns. D. 
D. a. fuscescena (di brows А variety with brown flowers, 
which are smaller (han those f the type. — 
D. aurea (golden) А synonym of D. онаи: T m | 
D. dubia (doubtful) jt, corolla , large thes of the 
plant, marked by many spots inside; {го} dilated, : 
racemes 
