DEC 
tained. 
navigation ; and other works on the praGtical {ciences. His 
works have been colle&ed and publifhed, as a complete 
courfe of mathematics, in four vo.umes, folio. He is chiefly 
efteemed for the eafy method which he had adopted of-ex- 
plaining and illuttrating difficult fubjeQs. 
ECHLANA, in Geography, a town of A fia in Albania. 
DECTALES, a people of the maritime Alps, along the 
coafts, W. of the Veiauni. 
DECIDUA Tunica, in Anatomy, the external mem- 
brane of the ovum, including the embryo, with the placenta 
and the other membranes. For the difcovery of this part 
we are indebted to Dr. Willtam Hunter. He proved that 
nuations of the uteriae blood-veffels ; and on the other, by 
being applied over the furface of the ovum, and forming in 
one part the uterine portion of the placenta, which is in- 
timately blended with the ramifications of the umbilical vef- 
els; he fhewed that it is thrown off from the uterus after 
the birth of the child, with the fecundines, and from th 
circumftance gave it the name of decidua. He was alfo of 
more particular account 
of this membrane, fee GENERATI of. 
ECIDUOUS, in the general, exprefles a thing apt and 
Decipuvovus Leaves, in Vegetable Phyfiology, are fuch 
as fall off in autumn, or at the approach of winter, as 
in moft trees and fhrubs of cold climates, ane fome tropical, 
ones; an entirely frefh crop being produced in the enfuing 
fpring. In North America the feafon in which this takes place 
derives its name from that circumftance, and inftead of au- 
How the falling or feparation of leaves from their 
branches is accomplifhed, has long been greatly mif : 
autumnal froft, for fome trees have their appropriate period 
of defoliation, feemingly independent of external caufes. 
The fall of the leafcan be confidered only as “a floughing 
or cafting off difeafed or worn-out parts,’? whether the in- 
6 
DEC 
jory to their conflitution may arife from external caufes, 
or from an exhaufticn 
m 
in the hornbeam, the beech, aud fome oaks, the fweihis of 
vary, and even accidental 
varieties, ratfed from feed, are occafionally more difpofed to be 
evergreen than is natural to ther {peci witnefs the 
Privet, Z m vulgare Hamel very juflly obferves 
that trees kiiied by any fudden caufe, asthuner, retain their 
leaves firml n the bran he reaion evidently is, 
that the vital principle, being perf-Gly extinguifhed. cannoz 
act to throw off the injured foliage. It is curious that Du 
- Hamel, evidently very anxious, and greatly embarraffed, to 
underftand the fall of the leaf, fhouid not have hit upon this 
fimple and evident explanation. S. 
D 
fall off in the autumn, and t 
winter feafon. Almott 
leaves on ihe approach of winter. 
Trees. 
Trees and thrubs of this fort are in general of hardy 
growth, being capable of fucceeding well in the full grourd 
in different fituations according to their kinds. Particular 
defcriptions of the different forts, as well as of their habits of 
growth, culture, management, and ufes, are given under the 
genus to which they refpeCiively belong. 
The proper feafons for removing this kind of plants from 
e nurfery or other places, and planting them ont where they 
are to remain, are either the early {pring or autumn, accord- 
ing tothe kind and the nature of the foil. In general, where 
the land is dry, the latter is the moft proper and advantage. 
ous; but in the contrary circumflances, the former may be 
the more advifeable. In the planting out all trees, fhrubs, 
and other plants of this fort, fufficiently large openings fhould 
be formed for the roots to be conveniently bedded in, after hav- 
ing | fuitably tri d di gtothekinds; and the mould. 
See Fruit and Forest 
advantage, efpecially when the weather is dry, to have them 
well watered occafionally, and moft of the forts fhould be 
ept fteady in their fituations by proper ftakes, as they never 
fucceed well where this is not the cafe, from their roots being 
deftroyed by being fo much agitated by the winds. 
DE TANTUM, a writ that lies on ftat. 38. Ed. IIT. 
c. 12. againit a juror, who hath taken money of either party 
for giving his verdict. It is fo called from its effeQ@, which 
is to recover ten times as much as he took 
. It alfo lies againft embraceors that procure fuch an in« 
quett. EMBRACEOR. 
, or Dezima, in Geography, a {mall ifland in 
the harbour of Nagafaki, on the coaft of Japan, fituated in 
N. Jat. 42°, and ceded to the Dutch, 
* DeEctM4, 
