84 
ON ARUM TRIPHYLLUM. 
time, and then washed on a sieve until all the fecula and 
soluble matter had been removed. The remaining fibrous 
substance, when dried at the temperature of 100° Fahr., 
weighed seventy-six grains. The washings and fecula were 
then thrown on a filter, and the latter, after being well 
washed with water, and dried at 100° Fahr., weighed one 
hundred and seventy-one grains, or 17.1 per cent. The 
root used in this experiment was collected on the first of 
November, and rasped soon after being removed from the 
ground. The roots collected on the 7th of May yielded 
10 per cent.; that obtained on the 8th of August, 11.3 per 
cent. It will thus be seen that, as the season progresses, 
the deposition of fecula increases from 10 per cent, in May, 
to 17 per cent in November, when the top has entirely dis- 
appeared from the plant. The roots taken from plants 
growing in different situations present various aspects. As 
a general rule, those plants that are found in moist, shady 
situations, have larger tops and smaller roots than those 
which grow in open places; and the latter always contain 
the largest amount of fecula. It has been observed, that 
when the plant is subjected to culture in a rich, somewhat 
elevated soil, fully exposed to the sun's influence, the root 
attains a much larger size, and yields a corresponding in- 
creased quantity of starch. It is also free from disease, 
which is apt to accompany the uncultivated, particularly 
when [growing in a very moist soil. This fact renders it 
probable that Jlrum triphyllum is susceptible, under proper 
treatment, of affording sufficient fecula to render its cultiva- 
tion profitable, with a view to supplying the market with 
arrow root. Dr. M'Call, of Georgia, in a note communi- 
cated to Dr. B. S. Barton, (Phil. Med. and Phys. Jour, 
vol. ii, p. 84,) states that he obtained 25 per cent, of fecula 
from the root of this plant. As has been previously stated, 
the greatest yield in my hands has been 17 per cent. Doubt- 
less the climate of Georgia may have had an influence in 
