i 
I 
6, Food habits of crabs of different a gm or sizes need to be more 
fully investigated both byj 
(a) the examination of stomachs of freshly-caught crabs, examined 
at once; and 
(b) by feeding experiments . 
7. feet blocks of various materials — sheet iron, glass, wood, and 
preferably in panels (one of each kind of material in 
concrete,^ 
same holder or at same station) — should be put out in order to study growth 
rate of organisms living on crabs, chiefly barnacles, bryosoa, bydrolda, and 
worm tubes. Information derived from such tests not only may throw light on 
growth rate and moulting frequency of crabs, but may also be of great value 
in determining the growth rate of marine organisms fouling ships in northern 
waters. Altogether too little data of this sort is now available, practically 
none at all, arid it undoubtedly would prove of great value in the near future 
in view of the much increased governmental Interest and activity in Alaska, 
8, hake study of environment of crabs i 
(a) Types of bottom. 
points may already have been observed 
(d) Enemies of crabs in hard shell stage as well as soft, commensals, 
and parasites. 
(e) Associated fauna ansi flora. 
(f) Hydrographic observations, temperature, and salinity, and what- 
ever chemical constituents, oxygen, etc., that it may be con- 
sidered desirable to note. Very probably the several salmon 
