200 THE NORTHERN MICROSCOPIST. 
Chicago, for a series of years, in which forty thousand deaths were 
reported with their causes, only two cases of trichinosis were 
reported. In Cincinnati, during the same period, not one case 
was reported. 
That the reported cases of trichinosis have resulted from eating 
uncooked meat shown to be inferior or rejected, and that thorough 
cooking entirely destroys this parasite and removes all danger in 
this regard from eating pork.— Scientific American. 
SEPARATING FORAMINIFERA FROM SAND.—TIf dried sponge sand 
is sifted into water, slowly, all the foraminifera will sink, and the 
sand will float on the water. A slide dipped under the floating 
film of grains will bring up only sand. You may safely skim off 
and throw away all that does not sink with a little stirring. Then 
the sunken part should be dipped out, about a dessert-spoonful at 
a time, into a small saucer, and water enough to just fairly cover 
them put in, and all floating grains stirred down. Then by a 
circling movement of the hand the foraminifera will come to the 
surface, and by gradually tipping the saucer they can be worked to 
one edge of the little pile of sand, and thence carefully dipped up 
with a rubber bulb pipette. In this way they are obtained almost 
pure. Only a little sand must be washed at a time, or not all the 
foraminifera will be got out, and very little water must be used, or 
sand will get mixed with them. Much water moves the light sand, 
but a shallow wave seems not to stir it, but yet rolls the shells along. 
—American Natuaralist. 
NEMATODES v. Osmic Actp.—The Nematode, Anguillula aceti, 
can live a long time in a liquid containing osmic acid. In the case 
of a female the eggs develope and hatch, and the embryos grow at 
the expense of the mother, until nothing remains of her body but 
the outer cuticle, which resists all attacks of the acid. When the 
young Anguillulze have pierced the cuticle and are free, they gener- 
ally die in a few days. 
A similar example is furnished by the larvee of the Diptera, Crz- 
ronomus plumosus Linn., which lives in water strongly mixed with 
osmic acid, owing to its cuticle resisting the reagent. 
SELF FERTILIZATION—that is, the formation of the seed by the 
agency of a flower’s own pollen rather than by that derived from 
some other flower of the same species, and brought to it by insects 
or other external agency—has, according to Mr. Darwin, the effect, 
after a time, of causing the disappearance—in other words, of 
preventing the formation of stripes and dots of color in the petals, 
and thus of tending to the production of self-colored or white 
flowers. As the necessity for attracting insects diminishes, so does 
the color which serves to attract them. Following Darwin, M. 
