324 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
These results shed uo light on the proteid composition of the tissue, except that 
the percentage of nitrogen corresponds almost exactly to that given by Chittenden 
and Hartwell 1 , for the nitrogen in elastin prepared from the neck bands of cattle. 
This fact has little weight, however, in view of the high percentage of ash present in 
the tissues under consideration. 
About 50 grams of the tissue were reduced to fragments, and washed repeatedly, 
by decantation, with cold water. The fragments were then washed with 90 per cent 
alcohol for 24 hours, and allowed to stand under ether, with frequent shaking, for 36 
hours. The material was then removed, freed from excess of ether, and dried in the 
air bath at 110° O., to constant weight. The dry fragments were tough and leathery, 
and could not be powdered. A portion gave with Millon’s reagent a light pinkish 
color. Analysis of this dried substance gave the following results: 
Quantity of 
substance 
(grams) . 
Constituents. 
Water. 
Carbon dioxide. 
Nitrogen. 
Ash. 
Grams. 
Per cent 
of hydro- 
gen. 
Grams. 
Per cent 
of carbon . 
Grams. 
Per cent. 
Grains. 
Per cent. 
.3229 
.3658 
. 3381 
.4695 
. 1988 
. 2227 
6. 84 
6. 75 
.5704 
.6476 
48. 18 
48. 28 
.0013 
.40 
.06140 
. 08568 
18. 17 
18. 25 
6. 80 
48. 23 
18.21 
.40 
By difference, oxygen. + sulphur = sum of means from 100 = 26.36 per cent. 
The high percentage of nitrogen shows at once that the tissue is not composed of 
elastin. Both the carbon and the nitrogen determinations would indicate that the 
tissue is a collogenous substance, and under appropriate treatment it has yielded glue 
of excellent quality. 
Brown University, Providence , Rhode Island. 
1 Abs. — Alien. Com. Organ. Analysis, vol. iv, 1898. [Appendix.] 
