254 PTILOTA : IMAGO EXTERNAL ANATOMY. 



ternal lobe, as it is generally called, is often of equal size 

 with the terminal portion of the lacinia, or the internal lobe, 

 and is here articulated both at its base and in the middle 

 (fig. 102 e e), and is generally termed thence the internal 

 maxillary palpus. In the order Orthoptera, this same outer 

 lobe is equally developed, but is not articulated, except at 

 the base (fig. 104) ; its inner surface is somewhat hollowed, 

 so that it falls upon the terminal lobe of the lacinia, and de- 

 fends it laterally. It is hence termed by Fabricius the galea, 

 a term applied theoretically by Strauss-Diirckheim to the 

 outer lobe of the maxilla; of all insects. In many insects the 

 two lobes are soldered together into a large flattened mem- 

 branous plate. Numerous other variations of form occur in 

 these two lobes, which, from their situation, are necessarily 

 the part most serviceable to the insect, and consequently 

 modified and adapted to the functions and habits of each of 

 these variations. Perhaps the most remarkable are those 

 exhibited by some of the leaf-devouring lamellicorn beetles, 

 in which the extremities of the lobes are very broad, horny, 

 and armed with several strong teeth, having somewhat the 

 appearance of a large double tooth (fig. 105), and by some 

 other beetles which feed upon the pollen or honey-flowers, 

 and in which the outer lobe of the maxillae is nearly half 

 the length of the body. In the stag-beetles it is prolonged 

 into a fine pencil of hairs, serviceable in licking up flowing 

 sap. It is at the external extremity of the stipes, and inter- 

 mediate between it and the base of the outer lobe of the 

 maxilla, that the palpus (or mp) of each maxilla is attached. 

 This is a slender appendage, somewhat similar in its con- 

 struction to the antennae, but much shorter, and composed 

 of fewer joints, varying in the latter respect from one to six 

 articulations. The latter number is often found in the 

 Hymenoptera, hut in the Coleoptera four appears to be the 



