HOW' THE SEED BURIES ITSELF IN THE GROUND.

Waikato Times, Volume XVIII, Issue 1544, 27 May 1882, Page 4

HOW' THE SEED B URIES ITSELF IN THE GROUND.

A PA.PKH tin. this subject was read at the recent meeting of the British Association . by Sir John Lubbbck. One of the most interesting parts in botany, he said, -was fclie considei-ation b'f ihe reasons -vyhich led to different forms, coloui'B, and structures of seeds, and ' it was, he thought, pretty well made out that a large proportion of those might bo accounted for dither as Serving to proicot'the seed or to assist in its conveyance to- a" place suitable to its growth. If the seeds of trees fell directly to the ground it was: obvious that very few of them would have a chance of growing. It was an advantage to them, therefore of which many availed themselves, to throw out wings, in consequence of which the wind wafted them to n. greater or less distance. Others were transported by animals, and others again were thrown to a g^cat distance by beautiful and wonderful contrivances in the plant. Some were enabled to. penetrate the earth, and others sow themselves in the ground. In one of the clovers (TriJ'o/tuiA suhtcrraneuvl), after the flower had faded, it turned downward and buried itself in the ground. The ground-nut of the West Indies, and more than one species of vetch, had the same habit. In the Eradunm or crane's bills, the fruit is a capsule, which opens elastieally, and sometimes threw seeds to some littlo distance. The seeds themselves were hi some cases spindle-shaped, hairy, and produced into a twisted awn. The number of turns on the awn depended on the amount of moisture. If a seed be laid upon the ground it remained quiet as long as it was dry, but as soon as it was moistened the outer fide of the awn contracted and the hairs surrounding the seed move outward, the result of which was to raise the seed into an upright position. The awn then gradually unrolled, consequently elongating itself upward with the result that if it was entangled among any of the surrounding [ hcibagc the seed was forced into the j ground. A still more lcmarkable case I was that of Utipn pemiutu, the seed of which was small, with a shaip point, and with stiff short liair» pointing backward. \ The upper end of the seed was continued | into a- fine twisted rod ; then came a j plain cylindrical portion attached at an i angle to the eoikseiew, and ending in a long and beautiful feather — the whole being about ,i foot in length. That end I was supposed by Mr Kraneis Darwin to, .tot vei y much in the same manner as I tli.it of /.roffudu. Mr Lubboek did not > doubt that tin end Mould Inn y itself in I the manner described by Mr Darwin, | but ho doubted whether it always did so. One fine day, not long ago, he chanced to i bo looking at a plant oi that specie's, and , around it wore ->o\oial seeds nioie or less Hi inly hit lied in the ground. Thcie was | ,i little wind blowing at the time, and it , him that the long fe.itlienng awn was admit ably adapted to catch the j wind, while, on the other h.md, it seemed | almost too delicate, to dine, the seed into j the giound, as dcsctibed by Mr Darwin. He there-tore took a seed and placed it upright on tho turt The day was pertcctly fine, and them could therefore be | no question of hygiorfcopio action. Ne\eithcless, when lie returned in a tew ! lioiii's' he found that the .seed had buried itM-lt sonic little distance in the giound. Ho repeated the observation several times, always with the same result, thus convincing hiimolf that one method, at any late, by which seeds bnry themselves is by taking advantage of the action of the w ind, and that the twisted position of the awn, by its corkscrew-like movement facilitates the entry of the seed into the gi omul.