4 BRITISH INSECTS 



of which is in one piece, the maxillae retain their 

 primitive jointed character, being severally composed 

 of two basal parts and two lobes. Moreover, each 

 maxilla carries a little feeler, termed a palpus. The 

 first maxillae are always separate, but the basal parts 

 of the second pair are generally more or less closely 

 united. For this reason naturalists usually refer to 

 them en masse as the lower lip, or Idbium. The only 

 other mouth-part that need be mentioned here is a 

 kind of skinny fold on the inner, or front, side of the 

 labium, which is known as the tongue, lingua or hypo- 

 pharynx. 



The would-be student of insects should form a clear 

 mental picture of the relative positions occupied by 

 these mouth-parts, and familiarize himself with their 

 technical names. He will then be able readily to 

 appreciate the nature of the changes, or modifications, 

 which fit insects to partake of different kinds of food ; 

 for the above generalized description applies only to 

 insects of the mandibulate or biting type, and there 

 are many kinds which feed either wholly or in part on 

 liquids. Some suck nectar from the flowers. Others 

 pierce the skins of plants or animals and extract the 

 sap or blood. Such methods of feeding obviously 

 demand special adaptations of the mouth-parts, and in 

 subsequent chapters we shall see how marvellously 

 these have been effected. 



In addition to the mouth-parts, the head of an 

 insect carries eyes and a pair of antennae. The latter 

 are often "feelers," used by their owner to explore 

 foreign objects ; but in many insects the antennae are 

 undoubtedly the chief seat of the sense of smell, while 

 they may possibly serve other senses as well. The 

 diverse forms of the antennae in different kinds of 



