[ 2^1 ] 
Remarks on the Impregnation of Vegetables. 
IpP A C H grain of pollen is a velTel filled with pul- 
py matter, in which are lodged a confiderablc 
number of fmaller grains, which may be called the 
impregnating corpufclcs (Figure 2, 3, 4, 5, 6, 7, 8, 
9, 10, II, 12, 13). Thefe are not vifible with the 
naked eye, but may be diftinguifhed with glafies of 
moderate power, if the grain be tranfparent, or if 
the pulp be forced out by compreffing the grain be- 
tween the talks. They are round, tranfparent, and 
nearly of the fame fize in all plants. They are con- 
veyed to the germen through the %le, which is 
furnifhed with internal duds for that purpofe j and 
in the clafs Syngenefia, and in the fmall plants of 
other clalTes, where the flyle is {lender and tranfpa- 
rent, they may be difHnguiflied in their paflage 
(Figure 19). The manner of their reception into the 
iifyle depends on the difpofition of its furface : our 
obfervation fell chiefly on thofe plants that have hairy 
ftyles or ftigmas ; and in thefe the corpufcles enter by 
means of the hairs, which are often found on the 
ftyle itfelf, fo that the ftigma mufl: not always be 
looked upon as the only recipient part, though it 
may, perhaps, be fo in mofl; indances. The hairs 
are fo many tubes open at the extremity for the 
reception of the corpufcles j they are ufually fhaped 
like a thorn, or prickle, widening towards the bafe. 
They are each of them furnilhed with a canal, or 
tube, which divides itfelf at the broader part of the 
hair, and enters the piftillum in two branches (Fi- 
gure 17) which run on till they join the longitu- 
dinal 
