8o THE BUTTERFLY'S TONGUE 



spiral muscular fibres, that wind in opposite 

 directions round its walls. 



When unfolded each of these long filaments 

 is found, under the microscope, to be fur- 

 nished with a row of exceedingly minute teeth 

 along the margins. It is the locking together 

 of the two rows of teeth of one half-tube to 

 those of the other that establishes the tubu- 

 lar arrangement of the proboscis. They form 

 a complete canal leading to the orifice of the 

 mouth. When not in use the proboscis is 

 coiled up and lodged beneath the head. 



The whole apparatus seems to act on pneu- 

 matic principles. It is adapted in every way 

 to suction. It pumps up the nectareous juices 

 from the cups of flowers, and is of necessity 

 of considerable length, in order to enable the 

 insect to reach the recesses in which the 

 honeyed store is lodged. 



Newport describes the action of the pro- 

 boscis of the butterfly as follows : t On alight- 

 ing on a flower, the insect makes a powerful 

 expiratory effort, by which the air is expelled 

 from the interior of the air-tubes and from 



