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PEOGEESS OF MICEOSCOPICAL SCIENCE. 
Diatomacece ahsorhed in their entire state hy the Boots of Plants. — 
Some very curious observations have been made by Professor P. B. 
Wilson, of Baltimore, U.S.x\., which seem to show that the DiatomacesB 
when applied to the earth in which corn was grown absolutely passed 
in their entire condition through the roots and were found in the 
stems of the corn. In 'Silliman's American Journal' (for May, 1876), 
Professor Wilson says : — " To demonstrate this theory, my friend G. I. 
Popplein, Esq., of this city, suggested the application of infusorial 
earth of the Richmond formation — found in large quantities on the 
western shore of the Chesapeake bay — to land sown in wheat. I have 
obtained straw from wheat so grown, and have found, after it has been 
treated with nitric acid, and the silicious remains placed on the field 
of the microscope, that it consisted wholly of the silicious shields of 
Diatomaceae, the same as found in the infusorial earth, excepting 
that the larger disks in their perfect form were absent (Actinocydus 
Ehrenhergii and Adinoptychus undulatus). My conclusions are that 
they, and there probably may be other forms, are too large to enter 
the root capillaries. During the coming summer I will attempt if 
possible to make micrometer measurements of both. The discovery 
of Diatomaceae in their original form in this wheat straw precludes 
the possibility of the infusorial earth having undergone any chemical 
change in the soil, either by forming chemical combination with the 
alkalies or the earths, or by suffering physical disintegration from 
any catalytic action of any salts present in the soil. In the particles 
of silica placed upon the glass slide, when they were completely 
separated from each other, the outlines of the individual diatoms were 
sharply and distinctly defined. On the other hand, when the physical 
action of ebullition with nitric acid was not sufficient for the com- 
plete separation of the particles of the epidermal shield, there was 
observed a marvellous interlacing of the various forms, showing that 
they were conveyed by the sap-cells directly to the section of the 
plant where they were destined to complete its structure. I have 
examined several specimens of straw, taken at random in the market ; 
the silica in each specimen consisted of plates, very thin, and truncated 
at the corners." 
The Markings of Fru^tulia Saxonica. — Mr. G. W. Morehouse, 
writing in the ' Cincinnati Medical Journal ' of J une, says that 
" Colonel Woodward's observations on this diatom are not accurate." 
We fancy, however, that the two observers have been treating of different 
diatoms. Mr. Morehouse says : — " Dr. J. J. Woodward, Assistant- 
Surgeon U.S. Army, Washington, D.C., publishes an article upon the 
markings of this fine test-object, in the London 'Monthly Micro- 
scopical Journal' of December, 1875. The article is illustrated by six 
photographs of this diatom. One thing is plainly evident, that how- 
ever excellent the photographic work may be, it fails in Dr. Woodward's 
