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the position hitherto assigned to this particular species, and indicates 
from the characters which he recognises in it the position in which 
he considers it should be placed. Not that any conclusion thus 
reached is final, for the species must then show no disposition to 
disagree with its new position by other characters present in its larva, 
pupa or imago. 
Dr. Chapman’s larval studies have been especially directed to the 
evolution of the larval proleg, and he has proved to us that the most 
generalised larvae are characterised by the possession of complete 
rings of hooks at the end of the ventral prolegs. As the larvae become 
more specialised the rings of hooks become modified, until at last in 
the higher, i.e., the more specialised lepidoptera, they exist only on 
the inner side of the ventral prolegs. The lines of modification here 
indicated have given Dr. Chapman important clues, which have led 
him to give many valuable suggestions and conclusions on the 
classification of lepidoptera. Undoubtedly, any other good larval 
character would prove equally fruitful in results to an intelligent and 
careful observer. 
Dr. Chapman is almost alone in his pupal studies, although more 
recently Dr. Packard has followed in his steps. The characters 
afforded by the maxillary palpus are most interesting, but form rather 
too complicated a matter to enter into here. Much easier to understand 
is the line of evolution as exhibited by the movable abdominal 
incisions in the pupa. It will be known to all that certain Orders of 
insects have no quiescent pupal condition, and that in such Orders, 
that part of the insect’s existence agreeing with the pupal condition in 
Coleoptera, Lepidoptera, Hymenoptera and Diptera is a more or less 
active one, and that the pupae (if we may so term them) of such insects 
have, therefore, an equal mobility of abdominal segments with the larva. 
The pupae of Hemiptera, Orthoptera, etc., are altogether as active as 
the larvae. 
The first necessity of insects is to live. Without the means of 
life there can be no development. But the exigencies of insect life, 
the dangers to which they are exposed in the course of their existence, 
and the general conditions of their environment make it clear that a 
quiescent period is likely to be of more service to them in the struggle 
for existence, and one can scarcely doubt that the quiescent pup* of 
almost all Lepidoptera run fewer risks than the active, but in many 
ways equally helpless, larvae. There can be no doubt, then, that the 
quiescent pupal condition which the Lepidoptera, in common with 
many other Orders of insects, have adopted, are of the greatest possible 
service to them in the “ struggle for existence,” and that it is, indeed, 
one of the chief causes of their great success in that struggle. 
Having pointed out that the quiescent pupal condition is a 
comparatively recent evolutionary product, acquired for greater 
protection, and so that development may proceed apart from growth, 
we may assume that the changes which have led to the present highly 
developed immobile pup*, as exhibited by many species, were neces¬ 
sarily slow. It is evident too, if we look back a little, that, as the 
segments of the larva are separated by movable incisions and the 
