10 REPORT OF THE COMMISSIONER OF FISHERIES. 
of this work in the past fiscal year are elsewhere shown. Further 
and practically continuous efforts will be necessary in order to supply 
deficiencies in existing knowledge and to determine the effects of 
fishing operations and regulatory measures on the mussel resources 
of particular water areas. During the year there were distinct ad- 
vances in experimentation, artificial propagation, and protection. 
An experiment in recovering young mussels dropped from infected 
fish retained in an inclosure gave a proportionate yield much greater 
than had been assumed to-be necessary to justify the expenditures 
for artificial propagation. Protection is, of course, a function of 
the several States, but the Bureau has done much to stimulate in- 
terest in the matter, and almost invariably the counsel of repre- 
sentatives of the Bureau is sought by the States in determining the 
portions of rivers to be closed against shelling operations for the 
protection of mussels. 
NEW SOURCES OF SEAWEED GELATIN, 
The investigation of gelatin derivable from seaweed was extended 
during the year to certain species of red alge of the Pacific coast, 
with the result that a new source of agar-agar of superior quality 
was disclosed. 
Agar-agar is the commercial name applied to a gelatinous product 
of certain red alge which is imported from Japan, China, and other 
places. The importations in 1919 amounted to nearly a half million 
dollars. Agar is used in making foods and confections, but its 
principal importance arises from the fact that it is a necessary 
medium for bacteriological work and is, therefore, essential to medi- 
cal laboratories and hospitals. Four species of alge from the Pacific 
coast were the subject of experimentation, and agar prepared from 
one of these tested at the Army Medical School in Washington was 
pronounced equal or superior to the imported agar, while another 
species yielded a product apparently of like quality. 
The discovery of domestic raw materials from which this important 
peculiar product may be made is a noteworthy event. In order that 
both Government and private interests may hereafter be independent 
of foreign sources of supply, further investigations should be con- 
ducted to determine the availability and locations of the proper alge 
on our coasts as well as the suitability of other species than those 
used in the experiments already made. 
ACTIVITIES OF THE BIOLOGICAL LABORATORIES. 
The situation with regard to the marine biological laboratories 
remains distinctly unsatisfactory. The anomalous salary conditions 
make it hopeless to secure and retain a competent scientific staff, 
and the positions are generally vacant. While the stations at Beau- 
fort, N. C., and Key West, Fla., have been virtually nonproductive 
during the past year, it has nevertheless been necessary to incur ex- 
penditures for maintaining the property. It has not, however, been 
practicable to prevent deterioration of the properties without more 
drastic curtailment of activities in other directions than seemed con- 
sistent with the accomplishment of a reasonable measure of public 
