CHAPTER XVII 

 The Insect Pollinators 



By far the most important insect pollinators of cultivated 

 crops are the bees of the order Hymenoptera. The bees 

 form a superf amily called Apina, the members of which as a 

 rule are known by the fact that under a lens the hairs which 

 cover their bodies are seen to be provided with many minute 

 barbs. In most cases, also, the first joint of the hind tarsi 

 is expanded and hairy, being adapted to carrying pollen. 

 The tarsi are the short joints at the ends of the legs, and 

 the first is next to the second large joint of the legs, which 

 in a great many bees is especially developed into a so-called 

 pollen basket. This may readily be seen by examining the 

 hind legs of a bumblebee or other large bee. The barbed 

 hairs over the body are obviously an adaptation for carry- 

 ing pollen, and they enable these insects to become the 

 most efficient of all pollen carriers. 



The bees, as a whole, are divided into two great groups 

 or families — the short-tongued bees ( Andrenidae) and the 

 long-tongued bees (Apidse). 



The short-tongued bees collect nectar and pollen from a 

 great variety of flowers, but they are not able to insert their 

 tongues into the long tubes of flowers in which the nectar 

 is deeply concealed. These bees, for the most part, build 

 their nests in the ground, burrowing holes into which they 

 carry a mixture of nectar and pollen upon which the larval 

 bees develop. Most of these short-tongued bees are very 

 small, and many of them may readily be found by a few 



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