180 



EVENINGS AT THE MICROSCOPE. 



THE SUCKER OF A BTTTTERFLT. 

 A smalt 



This specimen shows very distinctly that tlie two 

 sides are but semi-tubular, and as one pair of the op- 

 posing edges are open at each extremity, and the other 

 pair separate throughout, we are 

 able to discern very clearly the 

 ai-ray of hooks, by which the edges 

 are united at the will of the animal. 

 No trace of the curious little point- 

 ed barrel-shaped papillm is found 

 here, but I have seen it in other 

 examples. 



It seems highly probable, from 

 the observations of the excellent 

 anatomist just named, that the ex- 

 portion or one hait-cyiindor. haustlou of the Hectar of a flower, 

 which is effected with great rapidity and completeness, 

 is a process dependent on respiration, and connected 

 with the air-pipe that permeates each division of the 

 sucker. 



It will not be a very violent transition, if from the 

 sucking pump of the Eutterfly I carry you to the silk- 

 spinner of the caterpillar. Here I have a Silkworm in 

 the act of commencing its cocoon ; by inclosing which 

 in this glass tiibe, we shall conveniently have the insect 

 at command, and shall be able to view the process un- 

 der a low magnifying power and reflected light. Now 

 the grey face of the worm is presented to us ; and we 

 can see, below the edge of the head-shield, a short broad 

 upper lip, forming two blunt points. Below this is the 

 pair of strong brown mandibles, convex outwardly and 

 concave inwardly, each cut at its broad biting edge into 

 several teeth. Below these are two little points which 

 represent the maxillm, and between them a blunt 

 rounded knob, which is the lower lip {labium). 



