362 JOURNAL OF SCIENCE, 
English people scattered over the globe, no two could be found 
identical. This fact of individual variation is equally true of all 
other organised beings, animal or vegetable. We see it continually 
exemplified in ,the variability in physique, colour, disposition, and 
other points of our domestic animals, and the breeder whether he be 
an agriculturist or merely a fancier is quick to detect every trace of 
favourable variation and seeks to perpetuate and intensify it, while — 
similarly he does his best to eliminate whatever he considers 
unfavourable. We recognize the fact incessantly in our. gardens. 
We sow the seeds of many highly cultivated flowers such as stocks, 
wallflowers, 2uriculas, pelargoniums, &c., in comparative ignorance 
as to the results. And even though we know that the seeds were 
gathered from plants with certain well-marked characters, we by no 
means expect that all or nearly all the offspring will come true to 
kind. 1 need not insist further on the universality of the fact, for 
every one must admit it. | 
This tendency to variation appears at the first glance to arise 
spontaneously, and the phrase “spontaneous variation” has been 
used to a great extent, often very injudiciously. But no variation 
can be spontaneous; it is the result of some cause or causes which 
are mostly unknown to us, and it is only our ignorance of these 
causes which leads us to use such an incorrect phrase. It is unfor- 
tunately a very common practice, even among persons having a 
reputation for scientific attamments, to forget or to ignore the fact 
that every effect has its precedent cause. And this forgetfulness or 
ignorance is often masked by a term, the real meaning of which few 
take the trouble to examine for themselves. This term “ spontaneous 
variation” is tantamount to a confession on the part of the person 
using it, of ignorance of the real cause. 
2. The second great fact to which I would refer is the principle 
of heredity, viz., the tendency of all organic beings to reproduce 
others almost-—-but not quite—exactly resembling themselves. The 
principle in general is very universally accepted, though in certain 
details, such as the transmission of many physical and mental 
peculiarities among human beings, it is often denied. The truth is 
people are very unreasonable when any fact like this proves adverse 
to them. If their youngsters turn out to be bad tempered or early 
show any objectionable peculiarities, they don’t believe in the law of 
heredity as having anything to do with it; the nurse, or some other 
scapegoat, gets the blame of it.. Bnt if it is somebody else’s young- 
sters that are being discussed, then the question of heredity is at 
once invoked. Strong personal prejudice is often allowed to over- 
rule the reason. Fortunately, my subject does not require me to deal 
with these apparent exceptions to the principle. This principle of 
heredity is not in antagonism to that previously stated of the variation — 
of organisms, but both are closely co-related. Thus, we admit that, 
as a rule, the descendants closely resemble their ancestors, and that 
characteristics are transmitted from generation to generation. For 
instance, when we sow the seeds of wheat, we expect plants of wheat 
to grow from them, not oats or barley; and not only do we expect 
plants which we recognize to be those of wheat, but even of that 
particular kind of wheat—having certain peculiarities of grain, straw, 
suitability for certain soils and climates, &c.—from which our seeds 
were taken. At the same time, among a large number of plants of 
— ii, if-. e iae 
