MOUTH OF THE BUTTERFLY. 



315 



penknife ; occasionally they are so constructed as to form a tube by their 

 union, through which the liquid aliment is sucked up and conveyed into 

 the stomach. 



(827.) The mouth of the Flea, although described by Kirby and 

 Spence as forming a distinct type of structure, differs very little from 

 that of the Diptera described above, as will be at once evident on in- 

 specting the figure in the preceding page, reduced from a beautiful 

 drawing by Mr. W. Lens Aldous. 



(828.) In this insect the piercing organs are two sharp and razor- 

 like instruments (fig. 157, d d), placed on each side of the elongated 

 tongue (e), and enclosed in a sheath (c c), probably formed by pieces 

 representing the mandibles of mandibulate insects. Two palpi or 

 feelers (a a) and a pair of triangular plates (b b) complete this re- 

 markable apparatus. 



(829.) Another kind of mouth adapted to suction, and which seems 

 to differ more widely from the perfect form than any we have as yet 

 examined, is that which we meet with in Moths and Butterflies. This 

 singular organ is adapted to pump up the nectareous juices from the 

 cups of flowers, and is necessarily of considerable length, in order to 

 enable the insect to reach the recesses wherein the honeyed stores are 

 lodged. When unfolded, the apparatus in question represents a long 

 double whip-lash (fig. 158, a, 6, c, d) ; and if carefully examined under 

 the microscope, each division 



is found to be made up of Fi S- 158- 



innumerable rings connected 

 together, and moved by a 

 double layer of spiral mus- 

 cular fibres, that wind in 

 opposite directions around its 

 walls. When not in use, the 

 proboscis is coiled up and 

 lodged beneath the head ; but 

 when uncurled, its structure 

 is readily examined. Each 

 of the two long filaments 

 composing this trunk (which, 

 in fact, are the representa- 

 tives of the maocillce exces- 

 sively lengthened) is then 

 seen to be tubular ; and, 

 when they are placed in contact, it is found that their edges lock to- 

 gether by means of minute teeth, so as to form a central canal leading 

 to the orifice of the mouth. It is through this central tube, formed by 

 the union of the two lengthened maxillse, that fluids are imbibed. 

 Burmeister, however, asserts that the cavities contained in each division 



Mouth of a Butterfly. 



