1929 ] 
Present Trends in Systematic Entomology 
15 
I am fully aware that the present Mecca of many biologists 
lies in quite another direction — in the reduction of the 
phenomena of life to physics, chemistry and mathematics, 
but am not willing to concede that this will prove to be 
either the final goal, or the methodology which will lead 
to it. 
This attitude has arisen through the more or less tacit 
assumption that biology will finally find its place among the 
exact or mathematical sciences. This is regarded by the 
systematic biologist as a wholly undesirable if not impos- 
sible attainment. They have already cast aside any substitu- 
tion of numerical notation and symbols for binomial names 
and higher groups, as in no way simplifying the expression 
of taxonomic relationships. The reactions of organisms to 
light and heat, their growth and metabolism, the inter- 
actions of their genes in inheritance and many other pheno- 
mena which are due to similarities of their make-up are 
capable of mathematical expression as entities, so perhaps 
might be the combinations and permutations of these. Evo- 
lutionary change which is of primary importance to sys- 
tematics and phylogenetics on account of its historical 
aspect is a process of differentiation, recombination or 
emergence, and to believe that this has proceeded upon 
uniform or predictable lines does not aid in organizing the 
mass of data which taxonomy has so far accumulated. 
To observe the way in which one is viewed by his col- 
leagues is generally a fair method of discovering one’s short- 
comings and it may sometimes even lead us to discover our 
virtues. In either case it aids in the development of the 
submissive spirit which is a formidable asset in approaching 
the altar of Nature. As taxonomy is the oldest branch of 
natural history we may regard the newer branches as 
younger brothers and sisters whose criticisms are tinged 
with juvenile jealousy and largely to be discounted. Of these 
younger branches morphology is the first child of taxonomy ; 
indeed she is already becoming so Victorian in the eyes of 
the rising generation, that I hesitate to be seen smiling at 
her in public. Comparative morphology may be regarded 
either as the tool of taxonomy, or as a by-product of the 
latter ; unfortunately it is sometimes pursued independently 
which greatly limits its field of usefulness. Many of the con- 
