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of species living on leaves, may in itself have acted as such an influence, 

 without it being necessary that the change of food should have cooperated 

 with it ; however, this last mentioned change may also be regarded as eventually 

 acting upon larvae so strongly, that through it such an influence can arise. 

 The nature of the food, indeed, plays an important part among the requisites 

 of larval life ; a great many larvae stick exclusively to one kind of food, others, 

 when once accustomed to such a food, though properly speaking strange to 

 them, will rather starve than eat even the normal food of their species. The 

 larvae of many families are in fact limited to definite families of plants, and 

 for the peculiarities of these plants they possess a faculty of discernment that 

 is, indeed, wonderful to us. The larvae of Papilio Sarpedon L. very common 

 on Java, feed there, as far as is known to me, exclusively on the leaves of 

 the cinnamon-species. Now there stands at Batavia in an inner-court a Japanese 

 camphor-tree, doubtless the only one in Java, once cultivated there from seed 

 brought from Japan, and on the leaves of this quite isolated tree I found, to 

 my surprise, a larva of the said species. To my surprise, I say, because to 

 man the smell of camphor has surely nothing in common with that of cinnamon. 

 How was it then, I thought, that the 9 butterfly which laid eggs upon it, 

 could be so mistaken? Afterwards, however, I found out that Pap. Sarpedon 

 also occurs in Japan and that the larva there feeds on the leaves of the same 

 camphor-tree, and further that the camphor occurring in the leaves of the 

 camphor-tree, has, indeed, not yet been ascertained as an element of the 

 volatile oil of cinnamon-leaves, but that it has been ascertained in that obtained 

 from the root of the cinnamon-tree. This circumstance makes me strongly 

 inclined to believe that camphor is also very likely, though in a very small 

 quantity, present in the cinnamon-leaves, and that the Batavian butterfly was 

 probably not mistaken, but, being a finer chemist than our scientists, was 

 acquainted with the presence of this very small quantity in the cinnamon-leaves, 

 on which it had fed when a larva ; and therefore, finding the same smell in 

 the leaves of the camphor-tree, it also considered these leaves a fit food for 

 its offspring, and laid its eggs upon them. Besides, the cinnamon-tree and the 

 camphor-tree are both Latuvidcac and hence botanically closely allied plants. 

 But how did this butterfly know this fragance so well, unless as a remembrance 

 from its own larval state ? Many similar examples concerning the larvae of other 

 species and other plants afterwards became known to me. For this reason then 

 I thought it not too venturous to suppose that, as has been said above, the 

 difierentiating of the larvae of Callidryas Pomona F. and Terias Hecabe L. 

 may have arisen from a change in their food. And as each of the above 

 mentioned three pair of larvae in which I observed the said strong convergency, 



