286 
Proceedings of Royal Society of Edinburgh. [sess. 
We shall discuss each of these separately. 
1. The proportion of nitrogen in the Ulva. — The most interest- 
ing and important result of our analyses of the tissues of the weed 
— and certainly the most surprising one to us — is the extraordinary 
proportion of nitrogen which they contain. In the following table 
the percentage of nitrogen in some other (dried) seaweeds is com- 
pared with that of the ulva , as well as the ‘proteine,’ obtained by 
multiplying the percentage of nitrogen by the factor 6*25, 
Percentage of 
Ulva latissima , 
Nitrogen. 
6T8 
Proteine. 
38-625 
tChondrus crispus (Carragheen Moss), 
Bleached, from Bewlay Evans, 
1-534 
9-587 ) 
,, second experiment, 
1-485 
9-281 t 
Unbleached, from Ballycastle, 
2-142 
13-387] 
,, second experiment, 
2-510 
15-687 i 
«/ Gigartina mamillosa , from Ballycastle, 
2-198 
13-737 
Laminaria digitata , 
1-588 
9-925 
Rhodymenia palmata (Dulse), 
3-465 
21-656 
Rorphyra laciniata , 
4-650 
29'062 
Sarcophyllis edulis, 
3*088 
19-300 
' Alaria esculenta (Murlins), 
2-424 
15-150 
Fucus saccharinus , 
2-29 
,, digitatus , 
1-46 
,, vesiculosus, 
1-57 
, , ceramium rubrus, 
2-03 
Not only is the proportion of nitrogen in ulva extraordinarily 
high compared with that present in other seaweeds, but also with 
vegetables generally. Indeed, in nitrogen content it resembles an 
animal rather than a vegetable product, as will be seen from the 
-subjoined list of a few typical substances : — 
Animal. 
Percentage of Nitrogen 
about 
Meat (dry), 
10J 
Cheese (dry), 
7 
Milk (dry residue), 
5 
Vegetable. 
Peas, 
4-4! 
Clover Hay, 
3 
Wheat, . 
0.1 
• • • "2 
Meadow Hay, 
2 
* Thorpe’s Diet. Appl. Clnem. 
t Wiirtz, Did. d, Chim. 
