352 PRINCIPLES OF BOTANY; ETC. 
the roots of the pine trees, be not cleared away, as 
this weakens the trees, and pre-disposes them to the 
disease. 
| § 325. 
Debilitas, s. deliquium. Plants which suffer from 
debility have all their parts, stem, leaves, flowers, 
&c. hanging down quite flaggy and loose. Debility 
owes its origin to foul air, want of light, of leaves, 
or of moisture. Even to great intensity of light and 
other causes, which must be removed as soon as 
possible. 
§ 326. 
Suffocatio incrementi, or ill growth, is when plants 
grow little, and remain weak and feeble; their 
Jeaves in that case become pale, they shrink to- 
gether, and at last the whole decays. ‘This is dif- 
ferent from the last disease. ‘he causes of this 
are only accidental and may be removed, so that 
plants may still recover. These causes are, para- 
sitic plants and others, which twist round and at- 
tach themselves to their neighbours, and too glutinous 
soil. When those impediments to growth are taken 
off, the plants will soon be as well as ever. 
Darts 
Exulceratio. Ulcers are formed when a part of a 
plant becomes corroded, and discharges an ichorous 
liquor. Wounds degenerate into ulcers if not pro- 
perly covered, or if placed in such an unfavourable 
place, that rain or snow remain in it and become 
3 fusty. 
