94 BEES AND BEE-KEEPING. 



An important question now arises : How is this act 

 of sucking performed ? Some have supposed that the 

 suction originated in the mouth ; while Cook calls 

 the honey-sac the " sucking stomach," using an old, 

 but extremely misleading, title, for this wrinkled 

 membrane could no more exert suction than could a 

 balloon extract gas from the main. Comparing D 

 with E, Plate III., which are cross sections at the 

 same point, we see that the space (through which 

 the nectar must travel) surrounding the ligula, and 

 between the palpi and maxillae, is three times as 

 great in the former as the latter. This greater space 

 is obtained by arching the maxillae above the ligula, 

 and so causing the former to retreat from the palpi. 

 Here, then, is the origin of the sucking. The tube 

 is made to expand rhythmically above, the nectar 

 follows up into the space thus provided, and then, as 

 this contracts again, travels on into the pharynx, as 

 B, Fig. i g, will make clear. 



Second, How is nectar taken when smaller quantities 

 only are obtainable? A more minute investigation of 

 the ligula is now essential. 



The so-called sheath of the tongue is highly chiti- 

 nised, stout, and very elastic, while the hairs which 

 clothe it are broad at their bases (gh, I, Plate III.), 

 and pre-eminently suited to gather up syrupy fluids 

 by capillarity, but utterly unfit for collecting minute 

 quantities of nectar, only reachable, perhaps, by the 

 extremity of the tongue, as would be the case in 

 most flowers, especially those with a tubular corolla. 

 Here, then, another and surprisingly beautiful con- 

 trivance meets us. Taking a cross section through 



