i8o THE POPULAR SCIENCE MONTHLY. 



contact with the ripe summit of the seed-vessel, on which he rubs the 

 pollen from the last spike he visited ; and then, proceeding downward, 

 he unconsciously collects a fresh lot to carry away to the next fig- 

 wort. Of course, the wasp himself is not in the least interested in 

 these domestic arrangements of the plant whose honey he seeks; 

 all he wants is his dinner, but in getting it he is compelled, without 

 at all suspecting it, to act as carrier for the fig-wort from one spike to 

 another. 



Wasps are remarkably sharp and wide-awake insects ; and it would 

 be very difiicult indeed to take them in. Flowers that bid for their 

 attentions must provide real honey, and plenty of it. It is quite other- 

 wise, however, with flies. Those mixed feeders are the stupidest and 

 most gullible of all insects ; and many unprincipled blossoms have 

 governed themselves accordingly, and deliberately laid themselves out 

 to deceive the poor foolish creatures by false appearances. On most 

 mountain bogs in Britain one can still find a few pretty white flowers 

 of the rare and curious Grass of Parnassus. They have each five snowy 

 petals, and at the base of every petal stands a little forked organ, with 

 eight or nine thread-like points, terminated, apparently, by a small 

 round drop of pellucid honey. Touch one of the drops with your 

 finger, and, lo ! you will find it is a solid ball or gland. The flower, 

 in fact, is only playing at producing honey. Yet so easily are the flies 

 for whom it caters taken in by a showy advertisement, that not only 

 will they light on the blossoms and try most industriously for a long 

 time together to extract a little honey from the dry bulbs, but even 

 after they have been compelled to give up the attempt as vain they 

 will light again upon a second flower, and go through the whole per- 

 formance again, da capo. The Grass of Parnassus thus generally 

 manages to get its flowers fertilized with no expenditure of honey at 

 all on its own part. Still, it is not a wholly and hopelessly abandoned 

 flower, like some others, for it does really secrete a little genuine honey 

 quite away from the sham drops, though to an extent entirely incom- 

 mensurate with the pretended display. 



Most of the flowers specially affected by carrion-flies have a lurid 

 red color, and a distinct smell of bad meat. Few of them, however, 

 are quite so cruel in their habits as Rafilesia. For the most part, they 

 attract the insects by their appearance and odor, but reward their ser- 

 vices with a little honey and other allurements. This is the case with 

 the curious English fly-orchid, whose dull purple lip is covered with 

 tiny drops of nectar, licked off by the fertilizing flies. The very mal- 

 odorous carrion-flowers (or Stapelias) are visited by blue-bottles and 

 flesh-flies, while an allied form actually sets a trap for the fly's probos- 

 cis, which catches the insect by its hairs, and compels him to give a 

 sharp pull in order to free himself : this pull dislodges the pollen, and 

 so secures the desired cross-fertilization. The Alpine butterwort sets 

 a somewhat similar gin so vigorously that when a weak fly is caught 



