which have no permanent home and lead a hobo existence, with 
food, and warm, dry shelters. In the morning: a plentiful break- 
fast is ready, for during: the night this plant discharges its 
mealy pollen. The beetles and bugs in feeding become dusted 
with it, and in journeying on to other plants bring about cross- 
pollination. 
I wish I could go on and on telling you about this subject, it 
is so wonderful and so fascinating. If only the flowers and their 
insect servants were forty or fifty times larger so that you could 
not help, as you go about, noticing all these interesting things 
going on. You would be quite amazed at all you had missed. 
You certainly would be astonished at the giant bumble bee 
emerging from a flower of “butter and eggs” or toad flax 
with two great balls of yellow pollen attached to his forehead; 
or at that other kind of giant bee buzzing around with a double 
bag of milkweed pollen attached paper-clip fashion to his feet, 
together with half a dozen clips without the bags. You would 
watch with great anxiety the rifling of a bcx or two of Mimulus 
or monkey-flower pollen, wondering whether the bee could lift the 
lid all by himself. And then night, with its ghostly white flowers 
and great hovering honey-hunting moths ! But they are too small 
— you want something big to be interesting — like an elephant for 
instance. Only the more striking interests you — such a curious 
sights as a lot of moths caught in the slits of a bunch of flowers, 
because they were after honey that was meant for a certain kind 
of bumble bee that knew the technique involved and gave proper 
return. This is what happens in the case of Physianthus flowers 
outside their South American home. And the moths never get 
loose either. 
Every essay, we were taught, should have a climax, and so I 
have saved the two most interesting relationships between plants 
and insects for a “ proper ending”. These refer to a little moth 
and a tiny wasp. The former does its appointed task so well 
that the uninitiated would easily believe it had been trained for 
the job — and so it has— but not by man, but by the great trainer 
of us all— “The Struggle for Existence.” 
The yucca in one or another of its numerous species is a com- 
mon ornamental plant in most city parks over the country. In the 
west and southwest Spanish bayonet is one of its common names, 
as are also bear-grass and soapweed. Its pendant bell-shaped 
flowers are creamy white, of the general lily family type, with a 
three-parted pistil and six stamens. The seed pods each contain 
about 200 seeds. The pistil is terminated by a little pocket. The 
flowers expand and remain wide open only one night. At the same 
time the yellow, not over plentiful, sticky pollen becomes access- 
ible to visitors. So much for the stage and background. Now 
enter the actors in the persons of small yellowish white, metallic- 
sheened moths, Pronuba by name — Pronuba yuccasella in full. 
In the early dusk the female moths flutter about the yucca flowers, 
collecting pollen, not to eat, but of which theymake aball, which 
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