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their solution within the narrow compass of his own work. 
He confers with his fellow-workers in other orders, and finds 
that they too are seeking the solution of similar problems in 
the orders which they more particularly study, no matter 
whether they be plants, mammals, reptiles, or what not; 
they, too, have experienced similar difficulties; evidently 
they are working in a common field, the same laws are in 
operation throughout. By common consent a wider view of 
the situation is taken. Among others the geologist is con- 
sulted ; it is learned from him that this fair earth of ours was 
in remote ages—ages so remote that our present cramped 
ideas of time will not let us say how long ago,—was in a 
condition quite incapable of supporting life in its present 
form, yet living things did then exist upon it, and further, 
that in ‘‘modern”’ times the greater part of these British 
Islands, together with a considerable portion of the conti- 
nent of Europe, were for a considerable period covered by a 
great ice sheet, which rendered the. ‘existence of ‘their 
present fauna and flora impossible. The embryologist also 
has found that many creatures, which in their more mature 
condition have no resemblance to one another, are in their 
earlier stages so similar, both in appearance and behaviour, 
that it is almost impossible to distinguish between them. 
And even the chemist, whose sphere of operations would 
appear to lay quite outside the region of natural history, 
shows that some living organisms have in themselves the 
necessary elements for producing certain colour changes 
that we know actually do take place in nature. Thus does 
the light begin to dawn upon his work. He sees that 
difficulties which appeared to him to be insurmountable are 
capable of explanation by natural laws; he takes fresh heart, 
and accomplishes that which in his solitude appeared 
impossible. 
You are all of you familiar with the motto on the cover of 
the ‘‘ Entomologist :” 
‘* By mutual confidence and mutual aid 
Great deeds are done and great discoveries made.”’ 
We have looked upon these two lines so often that, I fear, 
we have come to overlook their import, but it has been by 
the mutual interchange of views and mutual assistance given 
that the great advance of the last half-century has been 
made, and so it will be by this same mutual confidence in 
each other’s work, and mutual aid to a common end, that 
the great discoveries of the future will be brought to light. 
