22 



GENERAL BIOLOGY 



piercing the tissues of plants and sucking out the sap. 

 Only incidentally is it used for gathering nectar. Its 

 very position and direction show it to be 

 unadapted to probing flowers. 



It consists of two pairs of lancet-like 

 organs, the modified mandibles and 

 maxillae, enveloped by the sheathing 

 lower lip, which is practically destitute 

 of palpi, and distinctly jointed: the 

 labrum is rudimentary. The accom- 

 panying diagram shows the parts as they 

 appear when somewhat separated 

 (fig. 1 6). 



Vesture. 

 The parts thus 

 far considered 

 have to do with 

 getting food. 

 We will next 

 consider that 



which has to do with the distributing of 

 pollen, the vesture, or hairy covering 

 The horny shell of the insect's body 

 if bare would carry 

 little pollen, but the 

 brushes of hairs 

 with which it is 

 usually clothed carry 

 pollen excellently and 

 serve well for im- 

 planting some of it 

 on the surface of the 

 stigma. 



FIG. 18. Pollen gathering hairs of the honey bee. 



FIG. 16. Diagram of 

 head and proboscis 

 of a bug (Pentato- 

 ma). a, antenna; 

 b, eye; c, labrum; 

 d, lancet -like man- 

 dibles; e, maxillae; 

 /, the jointed en- 

 sheathing labium. 



of the body. 



FIG. 17. Side view of abdomen 

 of a bee( Macropis) , show- 

 ing ventral pollen brushes. 



