PROCEEDINGS—PERTHSHIRE SOCIETY OF NATURAL SCIENCE. clxxxi 
minds in a practical form. The explanation is simple enough in 
itself,—over-population, consequent struggle for existence, variation, 
survival of the fittest, and inheritance of useful characters,—and yet 
no one had been able to fit the pieces of the puzzle together before. 
Since the publication of Darwin’s hypothesis, the whole trend of 
Biological investigation has been changed. Classification, distribution, 
embryology, and palaeontology have each assumed a new significance. 
The history of the individual has been recognised to be the history of 
the race in epitome, and classification is now based on genetic relation¬ 
ship. All facts of environment, such as climate, food supply, etc., 
as well as the inter-relations between plants and animals, are now 
studied as modifying causes. The study of fossil forms has received 
a new impetus, as it is here that we have to look for the links to fill the 
gaps which at present exist in the record. At first, biologists of the 
new school were inclined to despise the work of the systematists, as 
“ love’s labour lost,” but now it is seen that every new fact in animal 
and plant structure and distribution is of use in building up the 
the complete story of evolution. 
Since the time of Darwin, his work of philosophical biological 
investigation has been carried on by many earnest workers, prominent 
amongst whom are Huxley, Herbert Spencer, Haeckel, and Weiss- 
man, each of whom, however, regards Darwin’s conclusions from a 
slightly different standpoint. The last-named, in particular, takes 
exception to that part of the theory which deals with the inheritance 
of acquired characters. All that can be said with regard to this in 
the meantime is that we are still in complete ignorance with regard to 
the causes of variation and of inheritance. 
At first, as was to be expected, the theory met with a perfect 
storm of opposition, but this has gradually lessened each year, until 
now there can hardly be said to be any earnest thinker who does not 
accept the main facts of evolution as being conclusively established. 
As was natural, it was for long strongly attacked on the theological 
side, but now it has gradually come to be recognised that the con¬ 
ception of Creation by a gradual and orderly process of development 
is a much grander one than that of sudden and transitory acts of 
separate creation. To show how completely men’s views have 
changed on this subject, it will be sufficient to quote the words of the 
present head of the Anglican Church. Speaking of evolution some 
time ago, Archbishop Temple said :—“ It seems more majestic, more 
fitting of Him to whom a thousand years are as one day, thus to 
impress His will, once for all, on His Creation, and provide for all 
its countless varieties by this one original impress, than by special 
acts of Creation to be perpetually modifying what He had previously 
made.” 
(d) Palaeontology.— Little more than a century ago, fossils 
were looked upon as little more than mineralogical curiosities, or 
“Freaks of Nature.” Then William Smith detected their value to 
the Geologist as unerring guides to the succession of the stratified 
rocks; and Cuvier, Owen, and other comparative anatomists showed 
their relationships to living forms. It was not until the time of 
Darwin, however, that the study of extinct life was finally annexed to 
