SOLITARY BEES 
761 
Fig. 2.-—Short-tongued bees. 1. M acrnpis ciliata; a, female; b, male. 2. Halictus lerouxii; a, female; 
b, male. 3. Halictus hortensis; a, female; b, male. 4. Agapostemon radiatus a, female; b, male. 5. An- 
drena crataegi; a, female; b, male. 6. Andrena erythrogaster; a, female; b, male. 7. Nomia lietevoptera, 
female. 8. Megacilissa electa, male. 
partially digested pollen and nectar, which 
have been regurgitated. The bees of this 
genus tunnel in the pithy steins of bram¬ 
bles, and naturally are common on the 
flowers of blackbei’ries, but they are also 
often found on the blossoms of the stone- 
crop (Sedurn acre), prickly sarsaparilla 
(Aralia hispida) , goldenrod, mignonette, 
and collecting pollen on wild roses. Al¬ 
most equally primitive is the genus Sphe- 
codes,, except that they have acquired a 
short pointed tongue. They are nearly hair¬ 
less and are without pollen-brushes, and 
the food supply furnished their brood is 
similar to that of Prosopis. Great interest 
attaches to these two genera since they show 
the early stages of bees before they were 
much modified as the result of flower visits, 
and doubtless closely resemble the ancestral 
forms of the honeybee (Pig. 1). 
No other genera of the solitary bees are 
represented by so many species and indi¬ 
viduals as Halictus and Andrena. They 
show a marked advance over the preceding 
genera in their adaptations to flowers. The 
tongue is longer, the thorax is thickly pu¬ 
bescent, and the hind legs for nearly their 
entire length are covered with a dense 
scopa of hairs. They carry the pollen dry 
and chiefly on the thighs, while the honey¬ 
bees moisten it with honey and,pack it on 
the tibife. The ground bees are very im¬ 
portant in wild regions where there are no 
honeybees, and before the discovery of 
America probably played the chief role in 
the pollination of fruit bloom. On warm 
days in spring clouds of these bees fill the 
air around the bloom of the willows, plum 
trees, cherries, blackberries, and at times 
nearly all fruit trees and shrubs. Obser¬ 
vations made at the experiment station of 
Connecticut showed that in that locality 
they were by far the most common visitors 
to the apple, pear, quince, gooseberry, cur¬ 
rant, blackberry, and raspberry. For in¬ 
stance, out of 359 Hymenoptera taken on 
the sweet cherry 349 belonged to Andrena 
and Halictus. But in very large orchards 
