PROCEEDINGS 
OP THE 
MAY TO DECEMBER, 1871. 
GENERAL. 
1. 
Mustard and the Mustard Plant, 
By W. W. Stoddart, F.C.S., F.G.S. 
Read at the General Meeting on October 5th, 187L 
Perhaps of all the phenomena which come under the daily notice of the 
student of natural history none is more interesting than the power which 
certain groups of plants possess of elaborating powerful principles 
possessing strongly marked effects on the animal economy. Although all 
feed alike on the same mineral and gaseous elements, yet the products have 
the strangest variety and opposite properties. Some select sulphur, some 
nitrogen, some produce the most potent poisons or the most delightful 
flavours, whilst others only offer the most disgusting odour and repulsive 
taste. For instance the Solanaceae, the Umbelliferae and the^Rubiaceae 
may all be grown in the same soil and nourished under exactly the same 
conditions, and yet one will yield the deadly belladonna and the nutritious 
potato; the second will yield the grateful caraway and the disgusting 
assafoetida; from the third will be produced the refreshing coffee and the 
strengthening quinine. 
A very remarkable example of the natural selection of chemical principles 
exists in the group of plants to be noticed this evening, viz. : the Crucif erae 
or Cressworts. This order comprises the cabbage, mustard, cress, turnip, 
