76 BOTANICAL GAZETTE [JANUARY 
Asparagin, the amide of aspartic acid, has usually been given an important 
place in studies of protein metabolism in plants. ScHutzE has shown that it 
must be formed at the cost of amino acids, and according to his investigations 
it is a secondary product of protein changes and is not a primary building stone 
of proteins. TRreER cites considerable evidence in support of his contention 
that aspartic acid, the mother substance of asparagin, is formed from glutamic 
acid and leucine by oxidation processes. This agrees with the fact that where 
there is a strong accumulation of asparagin in germination the seed proteins 
show a high content of glutamic aci 
The author’s views regarding the part played by the carbohydrates in 
phosphatid preparations are of great interest, since it is impossible at the 
present time to fit them into any scheme of lecithin constitution, although 
TRIER himself has proved that phosphatids from seeds contain reducing sub- 
stances in chemical combination. He also found that the fatty acids increase 
and the phosphorus decreases as the content of reducing substances increases. 
This led the author to think that the regular phosphatid of SrRECKER and 
HoppE-SEYLER must be accompanied in plants by a substance of the pare eis 
of animal cerebrosides, that is, substances which furnish, as I 
as acids and nitrogen bases but no phosphoric acid. The following scheme 
shows the gradual building up of lecithins according to TRIER: 
Formaldehyde Triglyceride 
Glycolaldehyde Diglyceride 
Glycol Diglyceridphosphoric acid 
Diglyceridphosphoric acid glycol ester (N free lecithin) 
+NH; 
v 
fatty acid I 
glycerin 
ee 
is Ci. ad CH, * NH, 
Diglyceridphosphoric acid-aminoethylester (cholamin lecithin) 
+3CH,0H 
fatty acid I 
Phas hs soe 
No o CH. * ee * ee: 
OH 
Ideal lecithin or cholin lecithin 
