22 THE POPULAR SCIENCE MONTHLY. 



the plants or going to the nest, the bee at this rate would visit 

 six hundred blossoms an hour, or six thousand in a ten-hour day, 

 if she should work so long. On the five acres of hilltop where 

 my observations were carried on I judged that at least one hun- 

 dred of these bees were at work each day. Supposing that they 

 all worked at the above ratio, the mayflower 

 would receive six hundred thousand daily 

 visits. No doubt many of the blossoms are 

 visited more than once each day, and the 

 chances are certainly very good that each 

 blossom will be visited at least once during 

 the two weeks of its existence. 



Although the orange-banded bumblebee 

 FIG <> THE BEE FLY * s mucn tne most abundant visitor, two other 

 related species are often seen. The common- 

 er of these is a large and handsome Bombus* black, except for 

 two broad yellow bands one on the thorax and the other on the 

 abdomen. The other, which is seldom seen, is called by entomolo- 

 gists Bombus consimilis ; the thorax and front half of the abdo- 

 men are yellow, with the hinder portion of the abdomen black. 



By watching any one of these bees closely, one can see it stop 

 every few minutes to brush the pollen grains off from its tongue 

 and head, but no attempt appears to be made to collect the pollen 

 in the beautifully developed pollen baskets on the legs (Fig. 5). 

 These bees evidently visit the arbutus for the nectar it furnishes. 

 Although the bumblebees are much the most numerous and 

 important of the mayflower's invited guests, a few other insects 

 are found among the visitors. A 

 rather small, two- winged fly, with 

 a hairy, yellow body and black- 

 banded wings, often flashes, meteor- 

 like, from blossom to blossom. This 

 is the handsome bee fly of the genus 

 Bombylius,\ one of the earliest 

 spring insects. It has a very long 

 tongue, which readily reaches the FlG 7 ._ SE8IA MoTH 



bottom of the mayflower corollas. 



I saw one of these flies stop twenty seconds at a single flower ; it 

 thrust its tongue down on one side of the pistil, then drew it out 

 and pushed it down in another place, repeating the operation four 

 times. 



During the warmest portions of the brightest days the beauti- 

 ful sesia moths appear. They are sometimes called humming- 

 bird moths, because of their resemblance when flying to a hum- 



* B. terricola. f B.frateUus. 



