SPIRAL TUBE OF THE BUTTERFLY. 373 



varied in structure in different insects; as may 

 well be imagined, when it is mentioned that the 

 long and beautiful spiral tube of the butterfly, 

 by which it drains the juices of the flower, is, in 

 reality, composed of the maxilla?, or lower jaws. 

 In ordinary cases, the principal use of the lower 

 jaws appears to be to hold the food, while the upper 

 jaws bruise and crush it ; but their use, of course, 

 varies with their structure and modifications. 



The last part of the mouth is the labium, or lower 

 lip. This also is a very complicated organ, gene- 

 rally serving to close the mouth from beneath, like 

 the upper from above. It boasts, like the same 

 organ in higher animals, of a chin below it, called 

 the mentum, and on each side of it are a pair of 

 feelers, or palpi, like those of the maxilla?. In the 

 centre a little tongue-like projection is visible in 

 the figure, which is sometimes called the tongue, 

 but perhaps not correctly, if by that term is meant 

 the apparatus for tasting. The lower lip is as 

 much varied as the maxilla?. 



It would be impossible, without going too far 

 into minute technical details, to explain to the 

 reader how all these various parts of the mouth 

 are so modified, and altered, as to assume the very 



