306 Field, Forest, and Wayside Flowers 
pels them to carry it away with them to other 
dogbane flowers, 
The fly-caller seems unable to sip the nectar 
except by running his proboscis in between the 
long anthers, and just above the horny excres- 
cences on the corolla, When he attempts to with- 
draw, after drinking his fill, the three points lock 
together, like the jaws of a trap, holding the tip 
of his proboscis in durance vile. If the winged 
captive is big and strong, he gets free with a 
long and a_ vigorous pull. But small flies are 
often held prisoners till they die, probably from 
starvation: Sometimes one may see three or four 
of these hapless victims on one full-blooming plant 
of spreading dogbane. 
Among the prisoners one may often see a little 
summer-fly of dudish aspect, with body ringed 
with alternate bands of bronze and gold and wings 
of gauze shot with opaline colors. To what end 
is this bright little fellow sacrificed? Held as he 
is by the tip of his proboscis, his body does not 
come into contact with the plant, and hence it can- 
not be digested by the vegetable juices, as are the 
corpses of the sundew’s victims. The only possi- 
ble justification the dogbane can furnish for his 
taking off is that he has trespassed upon the 
