REPRODUCTION OF PLANTS. 
271 
The tenacity of life of some seeds after being discharged by the parent plant is 
astonishing! It is a well authenticated fact, that seeds may remain buried deep in 
the earth for centuries without losing their vegetative powers. On newly broken up 
land, or on earth dug out from a considerable depth in the earth, plants will 
appear which have never been observed before on the same spot in the memory 
of man. 
Seeds, like all the other members of a plant, have rudimental existence like 
the ovse of animals long before they are impregnated by the pollen from the 
anthers; but without impregnation they are wholly destitute of vitality. Fruits 
which are the investments of seeds may arrive at perfection though the seeds are 
absent or wholly defective. This is invariably the case with figs ripened in this 
country ; the seeds, although formed, are imperfect, because we have not got the 
male tree in cultivation. 
Besides the power of reproduction by seeds, plants have other modes of 
increasing themselves, viz. by offsets and suckers. And it is a remarkable fact 
that, in all cases where there is hazard of perfect impregnation by reason of the 
absence or distance between the male and female plants, or from the rigour of 
seasons, these kinds of plants are more prolific of viviparous progeny than others 
which yield great crops of seed. Instance the fig, the poplar and the English elm ; 
these if unfertile in seed are lavishly productive of suckers. 
Many plants reproduce or increase themselves both by seeds and suckers ; and 
it is observable that these properties are excited more or less according as either 
predominate. If many seeds come to perfection, few or no suckers will be produced, 
and vice versa. This circumstance is made available by practical men to procure 
whichever best suits their purpose of propagation. If a tulip or a hyacinth fancier 
wishes to increase his stock of bulbs, he must prevent the production of flower 
stems by cutting off the upper part of the old bulbs; this dismemberment will 
cause them to throw out an extra number of offsets from their bases. If on the 
other hand all offsets be displaced soon as they appear, both flowers and seed-vessels 
of the season will be correspondingly enlarged. 
The same effect takes place in the management of tubers or other subterranean 
stems. Those of potatos, for instance, are increased both in size and numbers by 
divesting the plants of their flowers soon as they appear. The Jerusalem artichoke 
and horse-radish plants, rarely produce seeds, because their strength is exhausted by 
the production of progeny under ground. 
The manner in which plants reproduce themselves viviparously, differs according 
to the constitutional character of the plant. Some, as the elm and poplar, are 
furnished with buds on their roots. These sooner or later sprout forth through the 
surface, and annually increase in bulk and height. Others, as the greater number 
of bulbs and tubers, multiply themselves by ejecting runners from the crown of the 
roots. Herbaceous perennials extend themselves in the same way, either by 
runners under ground as couch-grass, or above ground as the strawberry. Some 
yield living seeds from the vessel where they were matured, as is seen in some 
species of the onion family ; and others, like some of the lilies, produce little perfect, 
bulbs in the axils of the stem leaves. 
