248 NATURAL HISTORY MISCELLANY. 
De Candolle supposes that of the species now known and described 
about S aine are provisional, and that when all the species of America 
w adopted are as well studied as the European, the **good 
Species " sin be reduced to about one hundred; then the American spe- 
cies would scarcely be more than fifty. This is credible when we perceive 
supposed *‘ good species.” What will become of our — partic- 
ularly the Mexican species, when once worked out in that w 
I thought I had a very good character, eges by all fadi in the 
bud. The Quercus coccinea, wherever I found it here (Peoria) had a con- 
ical pointed tomentose five-ridged bud, with dui rows of scales, and I was 
sure I should never see it otherwise. Now I get from northern Illinois 
a number of specimens with the acorns and all the other characters de- 
cidedly those of Q. coccinea, but some of them with smooth round buds, 
just as in Quercus rubra. We have now about half a dozen species united 
in Q. coccinea ; the difference between Q. rubra and Q. palustris is so insig- 
nificant that the latter could be taken as a variety of the former, and per- 
ween the species as now accepted would be very Sosecistü. dos uer- 
cus bicolor seems to me to be a transitional form between e macrocarpa 
a . Prinus ; to acs former it is approximate by the often subulate 
scales, e pubescence of the lower side of the leaves, the buds, and the 
scaly bar the twigs, which are often corky in Q. macrocarpa. An 
exact — of the term ‘‘species ” has never been proposed. Since 
Darwin’s theory has made the stability of species d it has 
lost much of its importance; but we want a certain t m, be it species, 
or form, or race, or whatever it be: we want a name "m an object, that 
it may be understood. That is the task of species. I cannot see more 
in it.— FRED. BRENDEL, Peoria, 
T CONT. THE GERMS OF DiskEASE? — Dr. Tyndall, ina 
recent lecture, asserted: (1), that the dust in the air we breathe is largely 
composed of organic particles; (2), that they are the germs of plants 
like the yeast and such-like fungi; and (3), that they are the means by 
which epidemic diseases are propagated 
_ The editor of ‘‘ Scientific Opinion,” per that “each and all of these 
vations such as those of kompr Joly, Musset, Mantegazza and others, 
all go to show that the germs of many of the lower vegetable organisms 
which are familiar to botanists, dei pot presen in nd air generally. 
Thirdly, the hypothesis g small pox, scarlet 
