MR. A. W. BENNETT ON ^' DO FLIES EAT POLLEN?" 31 
l^atur-historischen Yerein fiir Eheinland und Westphalen in 
1869^':— 
As to flies, it has been till now generally admitted that they 
are exclusively destined to fluid nutriment. But in the summer of 
1867 I was somewhat surprised, while observing in my garden an 
Eristalis tenax upon a flower of' CEmthera media, to discover that 
it was eating the pollen. Eesting upon its middle and hind legs, 
it thrust out its fleshy proboscis like an arm, seized a morsel of 
pollen with the two valves which terminate the proboscis, and tore 
it away from the anther. Since the pollen-grains of CEmthera are 
tied together by elastic threads, that bit of pollen torn from the 
anther was attached to others by a band of threads, and the insect, 
in order to free its mouth from that inconvenient appendage, began 
to use its fore-legs. Raising both together towards its mouth, it 
seized between them the cordon of threads, and rapidly rubbing 
them one against the other, much as we do in washing our hands, 
succeeded in cutting the threads, and clearing them from its mouth 
and legs. Then it raised them again and seized the two valves of 
the proboscis, thoroughly cleaning them of pollen and the threads 
yet adhering to it ; and in about three seconds the work of cleaning 
was complete. At the same time the valves of the proboscis, by 
rubbing against each other, had masticated the morsel of pollen, 
and had conveyed the single granules into the channel of the 
labium, whence they were pushed into the mouth. It had hardly 
finished cleaning its proboscis and eating the first mouthful of 
pollen, when it seized another portion, and repeated each and all 
the operations I have described. It was so intent upon its meal 
that I was able to observe it in the closest proximity without its 
manifesting the slightest fear. 
"The quantity of pollen which dji Eristalis can devour in this 
way is surprising. Upon making a section of one and examining 
the stomach, it appeared very large, and was full of a yellow sub- 
stance which consisted of hundreds of thousands of pollen-grains. 
I have had since then many opportunities of observing the eating of 
pollen, not only in all the species of Eristalis, but also in the 
genera RMngia, Syrplius, Volucella, and Scatophaga. This chew- 
ing of pollen alternates with sucking honey if the flowers have any, 
and I am of opinion that the singular structure of the proboscis of 
flies cannot be fully explained without taking into account its 
double function of sucking honey and eating pollen. In the Tipu- 
* *• American NaturaHst," July, 1871, p. 290. 
