The Sources of Nectar and Pollen 371 
list of honey-plants at the close of this chapter. To the 
product which the bee makes from sugar from these sources 
the name plant honey-dew honey is given. 
Insect honey-dew. 
The main source of honey-dew is, however, not plant 
secretion but insect excretion. Certain plant-sucking 
insects, belonging to the order Hemiptera, such as plant- 
lice (Aphidse), scale insects (Coceidae), leaf hoppers (Jas- 
sidae), white flies (Aleyrodidae) and tree hoppers (Mem- 
bracidae), all belonging to the Homoptera, suck the juices 
of the various plants on which they are specifically parasitic 
and the portion of the sap not utilized by the sucking insect 
is ejected, falling on the leaves and stems of the plant and 
even running off to the ground below. Many of these juices 
are sweet and are gathered by bees exactly as they gather 
nectar, except that if nectar is available honey-dew is aban¬ 
doned. This is carried to the hive, ripened and sealed, 
making what is known as honey-dew honey. This substance 
is high in its content of gums and is a poor food for bees in 
winter. It was formerly believed that the honey-dew of 
some aphids was secreted from the tubular processes on 
the dorsal side of the abdomen but it is now established 
that it is an intestinal excretion, just as in the other families. 
Honey-dew is gathered by ants perhaps more than by 
bees. 
The sugars in honey-dew honey are the same as those in 
honey and the chief chemical difference is in the higher 
percentage of gums. The flavor is usually poor, and most 
honey-dew honeys are dark in color and granulate quickly, 
often before sealing. An exception is that from the sugar¬ 
cane leaf-hopper (Perkinsiella saccharidda) of Hawaii which 
rarely granulates. Honey-dew honey is probably much more 
common than is appreciated bv beekeepers,'for the excreting 
insects are present in millions every summer and probably 
many of our honeys contain small amounts of this substance. 
It is not unlikely that the variation in gum content of hon- 
