Cet E 
AMERICAN NATURALIST. 
Vol. I.— DECEMBER, 1867.—No. 10. 
<> 
DESMIDS AND DIATOMS. 
BY PROF. L. W. BAILEY. 
It is the purpose of the present article to present in a 
familiar way the more important features in the structure 
and history of some organisms in general but little known, 
the Desmiprace® and DraTomacE®, and to suggest a 
few reflections upon their habits and economical value, 
but more especially their importance, both in past ages 
and at the present time, in modifying the physical fea-. 
tures of the globe. 
Without entering into the facts of the discovery and 
history of these microscopic Algx, it may be sufficient to. 
say that they were originally included, together with two: 
other very interesting groups, the Polygastrica or Many- 
Stomached animals, ane the Rotatoria or Wheel-animal- 
cules, by the Prussian naturalist, Ehrenberg, under the 
common name of Infusoria. It is much to be regretted 
that a systematic classification, embracing numerous sub- 
families, genera and species, should thus have been in- 
troduced into scientific nomenclature, at a period when so 
little was really known of the true position of these organ- 
Entered li Act of Congress. in the year 1867, by the ESSEX INSTITUTE, in the 
Massachusetts. 
(505). 
AMERICAN NAT., VOL. I. 64 
