470 
ture and orographic features of the regions 
traversed accompanied Dr. Bell’s paper. 
The ‘Report of the Geological Section, 
for 1900-1901,’ was then presented by Mr. H. 
M. Ami, in which were pointed out the nine 
important discoveries in the Chazy, Trenton, 
Utica and Lorraine formations in the Paleozoic 
about Ottawa as well as those in the Pleisto- 
cene and marine clays, sands and gravels, etc., 
of the same district. 
H. M. Amt. 
SHORTER ARTICLES. 
ARSENIC TESTS. 
THE note concerning arsenic tests on page 
313 of the current volume of SCIENCE brings to 
my mind some experiments made while testing 
for arsenic in glycerol, an account of which is 
found in the Journal American Chemical Society 
for Nov., 1895. I found the destruction of 
the organic matter (before applying the Marsh 
test) by a mixture of sulphuric acid and nitric 
acid (80 to 1) caused a loss of arsenic in some 
samples but not in others. In one sample 
treated with this mixture it was found impos- 
sible to detect even added arsenic. My con- 
clusion at the time was ‘‘ that some at least of 
the samples contain, or are decomposed into, 
something capable of holding back arsenic. 
This leads to the query : What is the effect of 
the combined glycerol present in the toxico- 
logical examination for arsenic? May not the 
trouble with the glycerol be due to a decom- 
position product which could also be formed in 
the supposed case ?’?’? I have never had time to 
investigate this point myself, and as far as I know 
it has never been discussed in print. May not 
the trouble with the Marsh test as applied to 
beer be due to the same cause? I was able 
to detect arsenic in the above-mentioned case 
by adding the sample diluted with water di- 
rectly to the reduction flask. , 
A very simple, convenient and delicate 
method for detecting arsenic in glycerol is men- 
tioned by several writers. I am not certain 
who first applied it, but think it was Ritsert. 
The glycerol is diluted with an equal volume 
of water, HCl and zine added, and a yellow 
coloration obtained, if arsenic is present by ex- 
posing filter paper, moistened with either silver 
SCLENCE. 
(N.S. Vou. XIII. No. 325. 
nitrate solution (1 to 1) or saturated mercuric 
chloride solution to the evolved gas. A 
twenty-five cc. measuring glass is convenient 
for carrying out the test, the filter paper moist- 
ened with the solution being placed over the 
mouth. This test carried out with mercuric 
chloride is not as delicate as the Marsh test, 
but when silver nitrate is employed it is about 
five times as delicate. E. Ritsert (Pharm. 
Ztg., 1888, 715 and 1889, 104, 360 and 625) 
finds this test to show 0.001 mg. of arsenic in 1 
ec. of solution where the Marsh test only shows 
0.01 mg. in 1 ce. 
G. EH. BARTON. 
MILLVILLE, NEW JERSEY, 
Feb. 25, 1901. 
PRELIMINARY NOTE ON THE EMBRYOGENY OF 
NELUMBO. 
For two years the writer has had Nelumbo 
lutea under observation and has demonstrated 
among other points those enumerated below. 
The discoveries, and the conclusions arising 
from them, are of such importance that publi- 
cation in advance of the complete memoir 
seems advisable. They are as follows : 
1. The membrane surrounding the plumule 
has been shown to be, as conjectured by 
Wigand, a true endosperm arising within the 
embryo sac. 
2. The embryo is genuinely monocotyledon- 
ous in development and the conclusions of 
Mirbel are erroneous. The plumule arises 
laterally and at first there is but one cotyledon. 
Later this bifurcates to form the two fleshy 
bodies which since Mirbel’s. researches have 
been generally regarded as separate cotyle- 
dons. For the views of Barthélemy, Richard, 
Clos and others who have altogether denied 
the cotyledonary nature of the fleshy bodies, 
there is no foundation in fact. 
3. There is no primary root. The first roots 
are adventitious and spring from the epicotyl. 
Nelumbo, both in its anatomy and embryogeny, 
conforms to the type of the Monocotyledons and, 
probably with the other Nymphaeaceae, should be 
classified in the general vicinity of the Alismaceae. 
HARoLp L. Lyon. 
THE UNIVERSITY OF MINNESOTA, 
March 14, 1901. 
