3 14 
POPULAR SCIENCE REVIEW. 
touched, yet no such motion had been observed in Cereus , Mammillaria , and 
other allied genera of the order ; he had, however, noticed a similar motion 
in the stamens of the common garden Portulaca grandiflora , and in the 
Purslane, Portulaca oleracea. In another Portulaceous plant, Talinum patens , 
the expanded stamens fall down on the petals when touched, while, strangely 
enough, no trace of motion could be detected in Talinum teretifolium, though 
in a West Indian species which was found growing in a botanical garden in 
St. Louis the expanded stamens fell down on the petals when touched, and 
he thought it remarkable that this power should exist in T. patens and not 
in T. teretifolium . 
Mr. Meehan suggests that the objects of these movements may yet form 
an interesting study, pointing out that in Dioncea , Drosera, and some others? 
the motion had been found to result in some immediate benefit to the plant ; 
while in Mimosa , Hedysarum, and others, no such immediate benefit had 
been observed. In the case of sensitive stigmas, they had been supposed to 
have some reference to arrangements for cross-fertilization, but this he con- 
sidered doubtful on these grounds: — In the case of Mimulus ringens the 
stigmas expand, and the anthers disperse their pollen before the corolla is 
quite open, and pollen may be generally found on the stigmatic surfaces 
when the mouth exposes these parts to view. In Tecoma radicans, on the 
other hand, the lobes of the pistil do not expand till some time after the 
mouth of the corolla is open, and in many cases pollen-hunting bees had 
carried away all the pollen before these lobes had expanded. 
In cases where the expansion of the lobes and dispersion of the pollen 
were simultaneous, it was theoretically supposed that a bee or insect touched 
the lobes with its pollen-covered head or back, and that the lobes then 
closed against the admission of pollen on the withdrawal of the insect from 
the flower ; but he had found that the bees in the cases observed by him 
occupied but from three to five seconds in visiting a flower, while it took 
from thirty to sixty seconds for the lobes to close, and then they were seldom 
so completely closed as to render the reception of fresh pollen difficult. Mr. 
Meehan had therefore come to the conclusion that the hypothesis in relation 
to cross-fertilization was untenable, and that the real use of this motion in 
the economy of nature still remained an open and promising field to the 
future investigator. 
CHEMISTKY. 
The Formation of Organic Ultramarines. — De Forcrand has already shown 
that the ultramarines of different metals may be obtained by allowing the 
chloride of the metal selected to act upon the silver ultramarine, and the 
idea occurred to him that the process might be extended to the chlorides or 
iodides of different alcoholic radicles. The silver compound was heated to 130° 
for from fifty to sixty hours with an excess of ethyl iodide. After the opera- 
tion had gone on for from ten to fifteen hours the tube was opened, the product 
washed with alcohol, hyposulphite of soda, and water, and again placed in 
the tube with an excess of iodide. This process was repeated several times, 
