204 NAT URALEYSGLENGE. Marcu, 
Aroidez, in which the flowers are frequently proterogynous and as 
frequently proterandrous ; in Portulaca pilosa, the flowers of which open 
only in the sunshine, and yet seed abundantly when grown in the 
shade ; in Cuphea Zimpani (Lythracez), Lopezia coronata (Onagracee), in 
several species ot Lonicera, Phytolacca decandva, Lycopersicon esculentum, 
Hamamelis virginica, &c. A large number of the American Composite 
he asserts to be self-pollinated. He has observed pollen-tubes 
entering the clefts of the bilobed stigma before it opens; and the 
pollen-grains, even when large and brightly coloured, frequently 
fall on the stigma before any insect can possibly enter the flower. 
Mr. Meehan, indeed, goes so far as to say that whenever a speciesis 
unusually productive, he finds, as a rule, arrangements for self- 
pollination. An Italian botanist, Dr. Terraciano, states that in 
many species of Nigella, notwithstanding the conspicuousness of the 
flower and the presence of nectaries, the structure is adapted for self- 
pollination. According to Warming, all the Greenland and Iceland 
species of Euphrasia are self-pollinated. Even so decided a Dar- 
winian as Professor Caruel, of Florence, is inclined to doubt whether 
too much has not been taken for granted in the prevalent theory of 
the part played by the bright colour and sweet scent of flowers in 
attracting insects, seeing that, as far as we know, the visual and 
olfactory organs and perceptions of many animals are very different 
from our own. In particular, he calls attention to Sir John Lubbock’s 
observations on the different effect of colours on many animals from 
that which they produce on us; to the eyes formed of facets and to 
the ocelli of insects, and to their sensitiveness to the ultra-violet rays 
of the solar spectrum. Rosen asserts that even with many wind- 
pollinated plants, such as Carex and Festuca, self-pollination is therule. 
On the other hand, the orthodox view receives support from a 
very large nnmber of fresh observations which reveal adaptations 
clearly intended to promote cross-pollination by the agency of insects. 
In a series of papers in the Botanical Gazette and elsewhere, Mr. C. 
Robertson describes a large number of observations to this effect on 
American plants. Professor Halsted states that the flowers of the 
barberry are very rarely, if ever, self-pollinated, and calls attention 
to the remarkable irritability of the stamens of species of Portulaca, 
which promotes the scattering of the pollen over the bodies of 
insects visiting the flowers. The structure of the flowers of Arum, 
Dracunculus, Helicodiceros, Avisema, Amorphophallus, and other species 
of Aroidee, has been made a special study by several Italian 
botanists. The extraordinary simulation by the open flower of the 
appearance and odour of decomposing flesh, appears specially 
designed to deceive and attract necrophagous coleoptera and diptera, 
which aid in the carriage of pollen. Schulz asserts that in the 
family Sileneee of Caryophyllacee the proterandry is in many cases 
so marked as to render self-pollination impossible. Mr. G. F. Scott 
Elliot has, in the Annals of Botany, a very interesting paper on the 
