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BULLETIN OF THE BUREAU OF FISHERIES 
This applies also to the Ohio shad, a fish of potential importance and evidently not 
uncommon in season, but actually recorded at only two or three places in the whole 
basin (p. 171). It should be sought in late spring and early summer in all large 
streams of the Mississippi Basin. Even records of its presence anywhere would be 
of importance. 
7. Field studies should be made of the breeding habits of the larger catfishes. 
Practically nothing is known concerning the breeding of Fulton catfish, niggerlip, 
or goujon. What is known by direct observation of the breeding habits of the 
spotted catfish in fish-cultural ponds has been learned in very recent years (pp. 174, 
176, 178, and 179). 
8. A systematic study of the catfishes of the Mississippi, or any one of them, 
would be of great value. There are no adequate descriptons of any of the four 
larger and more important species — descriptions that give data as to change of 
color, form, and appearance with age, with season, or with habitat. Such information 
is particularly needed for the spotted catfish and the niggerlip (p. 178). 
9. The condition of the blue sucker in the lower part of the river should be 
determined. Since it is by far the most valuable of the suckers, excluding the buffalo 
fishes, and since it was once very abundant and important as a commercial fishery 
product, further experiments in its propagation by artificial means should be made 
if brood fish are still obtainable anywhere. Experiments made at Fairport are 
suggestive of possibilities in propagation. A study of its habits in any tributary 
of the Mississippi would be worth while. Why is it so rapidly vanishing (p. 184)? 
10. The distribution and relative abundance of the several species of carp suckers 
(genus Carpio) ought to be better determined; at least two species are generally 
obtainable in quantity in the Mississippi (p. 185). 
11. The drumfish offers an excellent problem for study. It is remarkable 
that a fish that is so widely distributed, so very abundant, so large at times, and so 
valuable should be almost unknown in respect of breeding habits and natural 
history other than as regards its feeding habits. One may well expect to learn 
something of interest concerning a fish that loves the swiftest current but is at home 
in lakes; regarding a fish that in one place is known as a 30 to 40 pound fish, 
in another as almost invariably a 2 to 3 pound fish, in still another as a fish that may 
weigh up to 6 pounds or over 12 but rarely between; or regarding a fish that in many 
places is valued as a food fish and in others is discarded and burned by the ton at 
some expense (p. 209). 
12. It is most desirable that there should be made a study of the conditions of 
occurrence of the yellow sand shell which is increasing in abundance in notable 
degree. This applies especially to the Mississippi River. 
13. The conditions of the niggerhead mussel should also be ascertained more 
definitely — where can beds of mussels be found in the upper river, in which very 
young mussels of this species are present in such numbers as to promise the per- 
petuation of the species (pp. 166 and 216)? 
14. The migration of fishes in the Mississippi River can readily be studied 
by means of tagging operations, such as were begun on a small scale a few years ago. 
The tagging and subsequent liberation of fish in large numbers is probably the most 
profitable method of inquiry that can now be applied to the fishes of a large river. 
The results should go far to settle disputed questions concerning migratory habits, 
besides throwing light upon rates of growth. Fishes of particular interest in regard 
