PROGRESS IN BIOLOGICAL INQUIRIES, 1926 681 
must have hatched. The crappie from this pond were reported to be in better 
condition than in other years, and we might conclude that the minnows were 
somewhat responsible for this. 
Another nest placed in bass-rearing pond No. E 1 had no survivors; and from 
1,000 fingerling black-heads (estimated) placed in another pond, none were 
recovered in the fall. 
The present conclusion is that this species will be of value in pond culture. 
Its superiority or inferiority to other forage minnows must be determined, how- 
ever, by more experiments, 
Good results also were obtained with the goldfish and golden shiners. In 
fact, the success met with the latter species was the factor that brought our 
production of bass fingerlings per acre up to an average of 5,000 fish. 
In the rearing ponds where golden shiners were used in numbers the produc- 
tion of bass fingerlings was over 6,000 per acre. 
As each of the 22 ponds must be taken up in this same way, we have so far 
collected a large number of miscellaneous data. It is evident that our work 
must be continued systematically and new experiments instigated as rapidly as 
possible. It is now necessary to make a thorough study of our material in an 
effort to establish correct interpretation and correlation. 
Mr. Nessrr. Mr. Lord mentioned that he had in mind a number 
of other investigations. We must realize that he had just one 
summer for all this work. There are one or two points that seem 
to me rather significant—regarding the efficiency of different depths 
in the various ‘ponds used. In. this connection’ I may say that the 
idea in fertilizing ponds, in addition to what food might already be 
supplied, is that you modify the growth of the organisms; but it 
seems to me that you should get the actual value of the sunlight 
effect on the organism you are trying to rear. 
In the days ‘when I was a botanist, I recall that the University 
of Nebraska was carrying on studies in the sand lakes of Nebraska on 
the sunlight at different levels in the water. The outstanding fact 
developed was that the ray of sunlight that affected the organism 
most did not penetrate far below the surface. It seems to me that 
in deeper ponds you would have to use more fertilizer, and fertilizer 
costs money. On the other hand, if you reduce the depth of the 
pond you would have conditions that may be unfavorable for the 
fish, so, of course, some sort of balance would have to be reached. 
I might add that in my own experience in rearing alge the amount 
of sunlight seemed to have a remarkable effect on the species. 
Mr. Lorp. We had not considered that in this summer’s work. 
The ponds are not very deep and when we applied fertilizer we 
just scattered it along the edges of the pond. Of course, a complete 
analysis of the result of using the fertilizer has not been undertaken. 
We have been endeavoring to cover a great deal of ground to get 
practical results as soon as s possible. 
O 
