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POPULAR SCIENCE REVIEW. 
decided differences of structure between tbe two. The former abounds in 
raphides, while in Wolffa there are none. 
The Function of Barren Stamens. — Dr. Maxwell M. Masters, in a short 
paper recently published, gives a capital account of a plant now at Kew (in 
the palm-stove), and which he refers to Dombeya angulata. The most in- 
teresting part of the description, however, is that which relates to the barren 
stamens of this plant and their functions. Some light, he says, is thrown 
on the use of barren stamens by an examination of this plant. In the 
fully expanded flower the upper angle or point of each petal is about on a 
level with the stigma and the lip of the barren stamen, the outer flat surface 
of which latter, as well as the adjacent portion of the petal, are often dusted 
over with pollen, the two stamens, nevertheless, being a considerable dis- 
tance beneath these organs. In less fully developed flowers, the barren 
stamens may be seen curving downwards and outwards, so as to come in 
contact with the shorter fertile stamens, whose anthers open outwardly, and 
thus allow their contents to adhere to the barren stamens. These latter, 
provided with their freight of pollen, uncoil themselves, assume more or 
less of an erect position, and thus bring their points on a level with the 
stigma, whose curling lobes twist round them and receive the pollen from 
them. “ The use, then, of the long staminodes seems to be to convey pollen 
from the short fertile stamens to the stigma, which, but for their interven- 
tion, could not be influenced by it.” Yide The Journal of Botany, March. 
Is Calluna Atlantica a Neiv Species ? — This question is answered in the 
negative by Professor Asa Gray. In a recent communication, he says that an 
examination of specimens from Cape Breton, Nova Scotia, and New Eng- 
land, does not reveal the naked pedicels, broader sepals, and “tip of flower- 
ing branches, not continued into a leafy shoot while the flower lasts.” 
These, it will be remembered, were the features on which the foundation 
of the new species was based. Yide Silliman’s American Journal, January. 
Vitality of the Seeds of Medicago Americana. — Some experiments, proving 
the wonderful vitality of the seeds of this plant, were lately made by M. 
Pouchet, the great advocate of the theory of spontaneous generation. 
Some of these seeds, which had been submitted to uninterrupted boiling for 
four hours, successfully withstood the high temperature, the outer integu- 
ment resisting the water, so that, when the seeds were subsequently sown, 
the young plants came up in from ten to twenty days. 
A Barge Collection of Fossil Plants, prepared by the late Mr. Nicol, is 
said, by the Journal of Botany, to have been purchased by the Trustees of 
the British Museum. The collection is a most valuable one, and has cer- 
tainly fallen into the best hands for the interests of science. 
Fossil Botany. — Mr. Carruthers, of the British Museum, has published, in 
the Geological Magazine and Journal of Botany some extremely valuable 
papers on the Gymnospermatous fruits of the Secondary Rocks of Britain. 
These papers are interesting not only for the full and clear descriptions they 
contain, but because they show how much may be learned of the structure 
and affinities of extinct plants, by the microscopic examination of sections of 
fossils. It is very remarkable, that the conclusions arrived at by Mr. 
Carruthers bear out, in some measure, those of Professor Unger. It seems 
that the fossil vegetation of the Secondary Period finds its nearest existing 
