SEEDS OF PLANTS. 
35 
(licles In every season of their growth, there appears only one 
time in the year when they are fitted to produce the seeds ; 
they are then quite loade»l with moisture, and, if laid open with 
care, w'ill be found inflated in several parts, in which the seeds, 
(surrounded with alburnum) are imbedded. Just before the ‘ 
barking season, iheie minor roots increase greatly, but do not 
swell into protuberances, as when the seeds are forming. 
'J'heir doing so must, I think, be owing to the sap being re- 
tained rather longer than usual for their formation ; for, in 
every instance with which I am acquainted, where alburnum 
is produced, it is effected by the momentary stoppage of the 
sap, which then agglutinates and produces a sort of jelly : not 
that I suppose the seeds to be composed of alburnum only ; 
even at first the eye can discover a difference, and much altera- 
tion is prod 'ced, in the first meeting and coalescing with the 
natural juices of the plant. The seeds are extremely dimiuu- ‘ 
tive when first protruded, and hardly to be discovered in any 
I microscope except the solar; but just before they leave the 
. radicle, and pour into the root, a common treble eye-glass can, 
(if united) shew them plainly. All the radicles contract at the part 
’ where they join the root. It is in this place the seeds are best discO- 
1 vered, in the narrow pass where, crowded together, numbers make 
I them so conspicuous. Formed of the freshest juices of the earth, Fnrmntinn of 
r which we call sap. just entering the plant, and producing a new 
t compound with its liquid, the first formation of the seed must 
: be simple ; but how different its future progress — how various 
* the chemical changes — how astonishing the innumerable solu- 
1 lutions that must be added to complete this extraordinary pro- 
« Auction. I have often, with amazement, viewed, and endea- 
tvoured to count, the number of vessels (changing almost every 
4 day) required to complete a seed, from the time it appears in a 
Ibud till it is fit for replacing in the earth, and capable of form- 
ing the embryo. Yet even these changes are not to be com- j„ices 
Ipared to the variety bestowed on its earlier existence, to the in- ‘he 
I numerable chemical combinations w hich must take place in the 
Meed, and around it, when passing from the root to the stem, in 
I that part (between the bark and w'ood) where it must equally 
D 2 partake 
