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ENTOMOLOGY 



worker, are used for cutting, scraping and moulding wax, as 

 well as for other purposes. The entire digestive system of the 

 honey bee is adapted in relation to nectar and pollen as food; 

 the proventriculus forms a reservoir for honey and is even 

 provided at its mouth with a rather complex apparatus for 

 straining the honey from, the accompanying pollen grains, as 

 described by Cheshire. The wax glands (Fig. 102) are re- 

 markable specializations in correlation with the food habits, as 

 are also the various cephalic glands, the chief functions of 

 which are given as : ( i ) digestion, as the conversion of cane 

 sugar into grape sugar, and possibly starch into sugar; (2) 

 the chemical alteration of wax; (3) the production of special 

 food substances, wftich are highly important in larval develop- 

 ment. 



Numerous special sensory adaptations also occur. In fact, 

 the whole organization of the honey bee has become pro- 

 foundly modified in relation to nectar and pollen. Many 

 other insects have the same food but none of them sustain such 

 intimate relations to the flowers as do the bees. 



Ant-Plants. There are several kinds of tropical plants 

 which are admirably suited to the ants that inhabit them. In- 

 deed, it is often asserted that these plants have become modified 



FIG. 264. 





Acacia sphcerocephala, an ant-plant, b, one of the "Belt's bodies"; g, gland; s, f, 

 hollow stipular thorns, perforated by ants. Reduced. From S'trasburger's Lehrbuch 

 der Botanik. 



