250 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
water can be drawn out, and in doing so tlie fish will be drawn into the receiving 
trough (C), which is placed Avith its top flush with the earth bottom in that part of the 
pond. The outlet for the water is an L-shaped pipe (shown at F, in cross-section 2), 
which is placed in the corner of the pond, the long end passing through the piling and 
underneath the pond embanhmeiit; the short end, called the stand pipe, stands close 
in the inside corner of the pond in.an ujiright position. The stand-pipe should have 
twoor more holes cut through (G, in section 1, plate 91) on the side nextto the receiving- 
trough, for the water to pass out in draAving down the pond. The size of these holes 
should be made in proportion to the size of the stand-pipe, which in turn should be 
governed by the size of the pond. The holes are to have a block of suitable size 
tacked over them to alloAv the pond to fill with water. A crib should be built around 
the stand-pipe, as shoAvn at E. In the front of this crib is placed the guard-screen 
(D), which should be 15 inches oimore in front of the stand pipe. 
The guard-screen should be from 14 to 10 inches Avide, using wire cloth 2 inches nar- 
rower. The wire used on the screen should either be of copper or well galvanized. 
The size of the mesh in the Avire should be suited to the size of the tish in the pond. 
The receiving-trough (0) should also be in proportion to the size of the pond. For a 
pond 10 by 40 feet a receiving trough 10 inches Avide, 6 inches deep, and 10 feet long 
would be a good size. A portion of the trough, as Avide as the guard-screen, should 
extend back and connect with the stand-pipe, the guard screen to fit doAvn on the 
inside of the trough. If the Avork is Avell done this Avill make every part secure, and 
there Avill be no danger of losing fish in drawing the pond. The trough or pipe carry- 
ing the water into the pond must be so arranged that the fish can not jumii from the 
pond into it. A good plan is shown at A, in the longitudinal section (plate 91) ; also 
at A, in rearing pond. This arrangement has been in use at Wytheville Station for a 
number of years and has given entire satisfaction. 
Stocling the rearing-ponds. — In stocking the rearing-iionds with trout fry I would 
strongly recommend doing it by degrees, especially Avhere the feeding is to be done by 
hand. I Avould put 500 to 1,000 fish in the pond and train them to take food readily 
before adding to them; that number of fish can generally find enough natural food in 
the pond to subsist upon until they can be trained to take the food that is given to 
them. Then add another 1,000 fish, and in about 10 days 2,000 more may be added, 
and so on till tlie ])ond is stocked Avith the desired number. When fish are first 
released in the ponds they seem to be Avild, and Avill run away from the food given to 
them; hence the necessity of teaching a few fish to eat first and then to add more 
from time to time. The first lot of fish being trained to eat, others will soon follow. 
The number of fish that a pond of a given size Avill support Avill depend upon the 
amount and temperature of the water and the amount of shade furnished, etc. In a 
pond 10 by 50 feet, and Avith water from 3 inches to 3 feet deep, I would not put over 
10,000 fish in any case, unless I Avas forced to do so for want of room. 
Paeliing eggs for shipment . — In iiacking trout eggs for shipment, they are' usually 
placed on trays in Avet moss. At the Wytheville Station, Avhence shipments are made 
to all parts of the United States and to many foreign countries also, the eggs are 
packed as follows: The number to be shipped is divided in from five to ten equal 
parts, according to the size of the shipment. If 30,000 eggs are to be shipped, I would 
use 10 trays large enough to contain 3,000 eggs each; if 15,000 eggs, I would have 10 
trays containing 1,500 eggs each; 10,000 eggs, 8 trays of 1,250 each, etc. If over 
