B U L 



B U L 



but the central flower-stem wrapped up at its 

 bottom in one membrane only, separating it 

 from the new bulbs near it. And on the exa- 

 mination of a large root of an onion produced 

 from seed in the spring, by stripping off the 

 leaves, and their fleshy bases one after another, 

 until two buds were rendered visible in the 

 centre of the fleshy bases of the' concentric 

 leaves that formed the bulb, it was found that 

 these bulbs were obviously formed and nourished 

 on the caudex by the stem, and its six or seven 

 concentric cylindrical leaves. Or it is supposed 

 from the difference in size, and seemingly in- 

 creased maturity of the central bulb, as well as 

 from the secondary bulb being placed between 

 the innermost and second circular fleshy mem- 

 brane, in these roots, as in those of the tulip, 

 that merely the central bulb may produce a 

 flower in the ensuing summer; while the lateral 

 bulb or bulbs only afford stronger and more 

 mature leaf-bulbs that in the succeeding summer 

 produce a flower. 



The caudexes or central parts of the bulbs, 

 from which the roots descend and the leaves 

 ascend, are placed differently in different roots; 

 in some above the knot or bulb, in others below, 

 and in others again in the centre. 



In the tulip the caudex lies below the bulb 

 whence the fibrous roots and new bulbs proceed, 

 the root dying after it has flowered ; the stem of 

 the last year lying on the outside, and not in 

 the centre of the new bulb. On examining a 

 root of this sort in the early spring, immediately 

 before it begins to shoot, a perfect flower may 

 be seen in its centre, and between the first and 

 second coat the large next year's bulb is be- 

 lieved to be produced; and between the second 

 and third, and the third and fourth coats, other 

 smaller bulbs are apparent, " all adjoining to 

 the caudex at the bottom of the mother bulb ;" 

 which are said to require as many vears before 

 they flower, as the number of tunics by which 

 they are covered. And similar different states of 

 maturity, it is supposed, mav take place in the 

 buds round the shoots of different fruit-trees, 

 the central one of which may afford flowers 

 the ensuing year, as on the spurs of apple-trees; 

 while those below require a greater or less 

 number before '• sufficiently mature to produce 

 organs of sexual generation," which is a secret 

 of great consequence in the management of trees 

 of the fruit kind. 



The root in the hyacinth differs from that of 

 the tulip, as the stem of the last year's flower is 

 said to be constantly met with in the centre of 

 the root, the new offsets proceeding from the 

 caudex below this bulb, and not from betwixt 

 any of the concentric coats of it, except the 



two exterior ones. For this reason the central 

 part is apt, from its decay, to destroy the 

 flower-bud unless removed from the ground at 

 the time the leaves decay. On this account it 

 has been supposed by florists, that these roots 

 perish naturally in from five to seven years after 

 flowering, while those of the tulip never die 

 from their age. 



The author of the Philosophy of Gardening 

 found, on examining roots of this sort in Sep- 

 tember, that in one that had seemingly flowered 

 during the summer, the stem was wholly de- 

 cayed in the centre of various new bulbs, 

 while in another, less in size, but compact, 

 which was supposed not to have produced a 

 flower, a central flower-bud was found in- 

 closed in many concentric fleshy bases of former 

 leaves. Hence he concludes that " the hya- 

 cinth root perishes annually or biennially, like 

 the onion, leaving behind it a succession of 

 leaf-bulbs or flower-bulbs." In the ranun ' 

 cuius, the caudex or claw-like root is believed 

 to perish annually, after putting forth a circle 

 of new claws from the upper part, round the 

 bottom of the flower-stem: hence the claws of 

 the old root, shrivelling as the flower advances, 

 disappear in the autumn, and the decayed por- 

 tion of the old caudex is visible below the new 

 claw-like roots: hence the supposition of the 

 old stem being drawn downwards by the new 

 root fibres. 



On these grounds it is concluded by Dr. Dar- 

 win, that " the concentric leaves that encircle 

 the stem of bulb-rooted plants, are the lungs 

 to the caudex, in the same manner as the leaves 

 are to the buds in trees; and that the caudex 

 with these leaves and the root-fibres constitute 

 a vegetable that produces " a viviparous pro- 

 geny of new leaf-bulbs, or a seminiferous pro- 

 geny in flower-bulbs, with a magazine of nutri- 

 ment in the fleshy base of each leaf." But 

 that the tulip affords only leaf-bulbs for four or 

 five years from the seed, and afterwards only 

 one flower-bulb with many leaf-bulbs annualy; 

 while the onion kind produce two or three 

 flower-bulbs in the first summer from the seed, 

 which in the second afford flowers and other 

 leaf-bulbs. And that it is probable, that all 

 bulbous roots, as the buds of deciduous treeSj 

 and perhaps evergreens also, are properly bien- 

 nial plants, as they rise in one summer and 

 perish in the following. 



When tulip or onion roots are planted deep 

 in the earth, vegetable cords about an inch in 

 length are seen sometimes to proceed from the 

 caudex beneath the base of the cylindrical leaves/ 

 and form new bulbs. This is likewise the case 

 in the natural growth of the roots of potatoes,, 

 3 E 



