14 MOUTH OF BUTTERFLIES AND MOTHS. 



would appear very doubtful. The principal modifica- 

 tions consist in the elongation of the tongue_, and of 

 the labial palpi and maxillae which form its sheath ; 

 and besides these the maxillary palpi are so greatly 

 reduced in size^ as to be scarcely perceptible in many 

 cases without a most careful examination. An in- 

 crease in some parts^ and a diminution of others^ are 

 therefore the changes for Avhich we must look in our 

 investigation of the truly suctorial mouths. These 

 are of three principal kinds^ of each of which examples 

 have been referred to above. 



In the Butterflies and Moths the sucking organ 

 consists of a long curled tube^ which reposes between 

 a pair of hairy cushions projecting from the front of 

 the head. In this their natural state we should have 

 as great difficulty in discovering the nature of these 

 organs^ as in recognizing the features of some well- 

 known friend recently fallen a victim to the fashion- 

 able epidemic of hair ; but on getting rid of these ob- 

 structions^ the difficulties to a great extent vanish. 

 We then find that the hairy cushions are jointed 

 palpij attached by their bases to a small lower lip^ and 

 by a diligent search we may discover the representa- 

 tives of the mandibles and labrum in the form of three 

 minute processes above the base of the spiral trunk. 

 The latter^ Avhich would appear to be the most un- 

 accountable organ of the whole^ is really formed out 

 of the two maxillae^ the basal portions of which^ 

 although small^ exhibit nothing remarkable in their 

 structure^ whilst the tips are produced into a pair of 

 long wrinkled tubes. Each of these tubes is furnished 

 along the entire length of its inner surface with a pair 

 of ridges^ which fit together exactly^ and thus the two 

 maxiUse adhere together to form a single organ with 



