280 Proceedings of Royal Society of Edinburgh. [sess. 
liquid was coloured green by a slight excess of hydrochloric acid, 
and a brownish flocculent precipitate was produced. 
By treating the ulva with alcohol or ether, the chlorophyll, etc. 
are only very slowly dissolved. In a preliminary experiment some 
of the dry seaweed was submitted to the boiling reagent in an 
extraction apparatus for a week — ether first, and alcohol later — 
but at the end of that time it was still green in parts. 
In a later experiment, 14 grms. of the ulva — washed, dried, 
and roughly powdered — were boiled in a flask with inverted con- 
denser for a week with alcohol. Each day the alcoholic extract 
was filtered off and distilled from the same (tared) flask, the 
distillate being again employed for the extraction. 
The dried alcoholic extract weighed 2*35 grms., or about 17 per 
cent, of the weight of the original dried seaweed. 
What remained of the latter was then dried and digested in the 
cold for eight days with a 5 per cent, solution of caustic potash. 
The liquid was then filtered off through a weighed filter, and the 
residue of seaweed collected on the latter, well washed and 
weighed. It amounted to about 7 grms. 
On the supposition that alcohol removed all the chlorophyll, 
fat, etc., and the caustic potash the albuminoids, the composition 
of the dried seaweed may be represented thus : — 
Chlorophyll, fats, etc., 
• 17% 
Albuminoids or ‘ proteids, 5 
• 33,, 
Cellulose, ..... 
• 50 „ 
100% 
If the percentage amount of nitrogen found in the ulva be 
multiplied by the factor 6’25 (often employed for calculating in 
such cases the ‘Proteids 5 ), the result is 38-6, which is not very 
different from 33, and it must be remembered that the experiment 
was only roughly quantitative. 
Bacteriological Examination. 
From the chemical examination of the products of the ferment- 
ing ulva , it seemed probable that it was attacked by at least two 
