76 The Botanical Gazette. | March, 
The theory that, by whatever means gained (by the crossing 
of individuals if possible, if not by self-pollination), the great 
- object of plant-life is the production of seed, the continuance 
of its species, receives further support by the presence in 
many of the forms, most beautifully adapted to the visits of 
insects, of cleistogamic flowers. These are minute, nevet- 
opening flowers whose stamens produce very little pollen 
(from 100 to 400 grains in contrast to the 243,600 of Legnto- 
don or the 3,654,000 of Peony), but the anthers are in close 
contact with the stigma, none of the pollen is wasted and the 
inevitable self-fertilization causes the ripening of seed enough 
to secure the the existence of the species, if for any reason 
the more conspicuous flowers are not visited. Kuhn enumet 
come at last in the form of buzzing bombuses for the tWO— 
species of Monotropa, a tiny fly for the little shore pin weed 
(Lechea thymifolia), clumsy bugs for the honeyless, dull- 
colored purple trillium (Trilljum erectum), pollen eating bees. 
and flies for the homely ragweed (Ambrosia artemisizefolia-) ae 
During the last spring, ‘summer, and autumn I caught @ | 
thousand insects on one hundred ‘and forty-three species a 
plants (one of a kind on each). One hundred and thirty-one 
of these flowers are visited by Hymenoptera, fifty-seven by : 
Lepidoptera, sixty-two by Diptera, seven by the ruby- 
throated humming bird. I shall not soon forget the first” 
2 aining dry the nectar cups of ie 
columbine (Aquilegia Canadensis); nor the daily visits which : 
he afterwards made to : trumpet 
the 
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