BEES' TONGUES, AND HOW THEY SUCK HONEY 73 



ascending scale, beginning with the bifid-tongued 

 species, through those with the short spear shaped 

 tongues to the higher forms, which have this 

 organ elongate and parallel-sided. 



The tongue is the central organ of an elaborate 

 combination of mouth parts, which I will now 



FIG. 19. 



try to explain. If we turn a bee's head over 

 and look at its underside we shall find a deep 

 cavity, filled up with the base of this combina- 

 tion which fits into it. If we extend the tongue 

 (a humble bee is a good subject on account 

 of its large size, fig. 20) so as to draw its base 

 out of the cavity, we shall find that in the edge of 

 each side of the cavity there is articulated a short 

 rod (20, A), more or less dilated at its apex, called 



