SCIENTIFIC SUMMARY. 
431 
respect to tlie function of these mosses, lie cannot do better than quote Professor 
Schimper’s words. He says : — u Unless there were bog mosses, many a bare 
mountain ridge, many a high valley of the temperate zone, and large tracts 
of the northern plains, would present a uniform watery flat, instead of a 
covering of flowering plants or shady woods. For just as the Sphagna suck 
up the atmospheric moisture, and convey it to the earth, do they also con- 
tribute to it by pumping up to the surface of the tufts formed by them the 
standing water which was their cradle, diminish it by promoting evaporation, 
and finally, also by their own detritus, and by that of the numerous other 
bog plants to which they serve as a support, remove it entirely, and thus 
bring about their own destruction. Then, as soon as the plant detritus 
formed in this manner has elevated itself above the surface water, it is 
familiar to us by the name of turf, becomes material for fuel, and all 
Sphagnum vegetation ceases.” 
The Cross-Fertilisation of Scrophularia nodosa. — It is probable that the 
dichogamy of the flowers of Scrophularia has already been observed and 
published, but it was new to Professor Asa Gray until pointed out this 
season by his assistant, Dr. Farlow. The arrangement is thus: — In the 
freshly opened blossom the upper part of the style is bent forward so as to 
bring the stigma, now ready for pollen, just over the patent lower lip of the 
corolla : the anthers, not yet dehiscent, are out of sight toward the bottom 
of the corolla, the filaments being strongly recurved or doubled over. In 
the blossom a day or two older, the stigma has dried up, the style become 
flabby, and the filaments have straightened so as to bring the four anthers 
up to the gorge of the corolla at the base of the lower lip, just back of the 
now withering stigma. The transversely dehiscent anthers are now widely 
open. The flowers are visited by honey-bees, which barely insert their 
heads into the gorge of the flowers ; the chin or throat of the bee, coming 
into contact with the lower lip of the corolla, is necessarily dusted with 
pollen from the older flowers ; and this pollen, in the passage from flower to 
flower, and plant to plant, is inevitably applied to the stigma of the freshly- 
opened flowers, which alone is in condition to receive it. The nectar sought 
by insects is here secreted abundantly by the corolla, at its base on the 
posterior side, and to some extent by the disk which girts the base of the 
ovary. The posterior face of the scale which represents the anther of the 
fifth stamen is apparently glandular, but hardly, if at all, nectariferous. 
Bees plunge their proboscis to the bottom of the flower. — Silliman’s American 
Journal for August. 
So-called Mimicry in Plants. — Professor Dyer read a paper on this subject 
before the British Association at Edinburgh. He pointed out the broad 
distinction existing between the mimicry of animals and what is called by 
that name in the vegetable kingdom. In the first case, the animal and 
what was mimicked were always found in close association. On the other 
hand, the plants in which a mimetic resemblance was observed were seldom 
found in the same neighbourhood. A striking resemblance in foliage would 
be found between a plant of the group of leguminosae and another belonging 
to that of compositse j as also between distinct varieties of ferns, though 
existing under entirely different conditions and indigenous to widely- 
separated portions of the globe, and in the leaves of several species of 
