which j'ou will find has a very powerful odour. Now this 

 oil is identical with that which exists in the common meadow 

 sweet {spircea ulmaria), and is, therefore, peculiar!}' interest- 

 ing to chemists as being, so to speak, a natural product, 

 artificially produced and connecting spiroea oil with the 

 alcohols. These facts were known to chemists for j'ears, but 

 it was only in 1850 that Liebig made an observation which 

 brought salicin within the domain of the naturalist, namely, 

 that the larva of a beetle, the chrysomella populi, which lives on 

 the poplar and willow, secretes, especially when frightened 

 or irritated, spiroea oil from some small glands near the tail. 

 There can be no doubt that this is produced by the oxidation 

 of the salicin of the willow bark eaten by the larva. Processes 

 of oxidation in the animal body are so numerous, that such an 

 action is not in itself surprising, but we are led to ask why 

 this larva is furnished with organs specially for secreting this 

 oil, and why it is ejected when the creature is alarmed or 

 irritated ? Has this larva any special enemies to whom the 

 smell of spircea oil is ofiensive ? This and other interesting 

 inquiries naturally suggest themselves, and that which began 

 as a chemical research ends by being a subject for the 

 naturalist. Need I say more ? When any subject is brought 

 before us by our Members, do not let us ask too curiously, 

 how does this come within the scope of our Society? Every 

 well observed fact is a stone in the great fabric of truth, and 

 which of us shall say when it will find its proper place in 

 that edifice where alone its true use and beauty can be under- 

 stood. 



