are formed in the Root alone. 187 



be before the biul is quite complete. I forgot to mention that 

 in most j^/-5 tlie bark juices are of a deep yellow brown, and the 

 seeds of a most beautiful yellow white. All this evidence, strong 

 as it is, is nothing to the perfect conviction the mind receives 

 when in the arum the seeds are seen running up the middle 

 flower-stem, and thus passing into each separate seed-vessel, or 

 still plainer if possible in the larch, where a vessel is formed on 

 purpose for transporting them to their proper situations. As 

 these reasons are, I think, all sufficient, 1 will noc trouble the 

 reader with all 1 bad prepared, but show, what is almost as plain, 

 " that the pollen also is contained in that which forms and fills 

 the intermediate spaces between the vessels which contain the 

 seeds." 



Malpighi took these vessels for air-vessels: hut, whatever they 

 are, after the seeds have deposited themselves into the seed- 

 vessel, and that it has closed on them ; i/iis powder, which had 

 before visibly run from the bark to the middle of the pith (now 

 first receiving the coloured juices, which give tlieni a yellow 

 lint) , immediately proceeds up the middle space httween the hiids, 

 and enters them at the upper part instead of the under. In this 

 specimen they cannot be seen to enter the pollen cases, but in 

 the arvm, they are seen to proceed i/p the p/aiit and enter the 

 stame/i in the same maimer as the seeds had done just before in 

 their appropriate places. I have many reasons to suppose that 

 the pollen powder is formed in the tap root; but this is not a fact 

 of which I am so perfectly assured as of the preceding circum- 

 stance. I have certainly taken it from iheiice, but A'ery unlike 

 the seeds ; the alteration of its form is so very great as to make 

 it much more dijficult to trace ; it is most easy, however, to follow 

 its progress as soon as it reaches the olhurnum ve^'Se/s. That 

 the pollen receives its colouring liquor from the atmosphere, 

 there can be no doubt ; I have seen it enter the liairs, combine 

 with the powder in the pith, dye a part of the pith with the same 

 tint ; and when the pollen is perfectly coloured, I have seen it 

 run into the top of the bud, slowlv proceeding to its des.tiiiation. 

 This is all to be traced point bv point with a si>?L>Ie Jiiicroscope. 



In taking a ])lant where the male and female flowers are se- 

 parate, the balls jjass to the female flower, the pollen to the 

 male. In all theirs this is admirably viewed in the early part 

 of the formation of the bud. In real male trees the balls never 

 appear, and iu female plants the pollen is never discovered ; both 

 seeds and pollen are often found in double flowers, where they 

 never come to perfcctiou; but here it is the impregnation of the 

 seeds that fails ; I conjecture that the impregnation is not re- 

 quired for the formi?i<r the seeds, or at least the embryo of the 

 seedfhvil for itHjiature and Jin is h ; does it not here maintain 



some 



