18 BULLETIN 908, U. S. DEPARTMENT OF AGRICULTURE. 
classes copepods, which are approximately one-eighth inch long, as 
macroscopic forms of sea life. 
2. Schizopods,! or “‘shrimp”’ (Pl. XI), are the larger anne eecopscal 
forms on which the fish feed. 
Frepy Fisn. 
Fish which have been feeding extensively on either of the two kinds 
of food known to the fisherman, as “‘red feed” and “shrimp” may be 
designated as ‘‘feedy fish.’’ While there is little difference in the 
action of the two kinds of feed in rendering the fish unsuitable for 
packing, fish that have been feeding upon “‘red feed’? become broken 
and deteriorate a little more rapidly than fish that have been feeding 
on shrimp. Bacteriological examination of the feed showed that the 
bacterlum commonly associated with copepods grows faster and 
produces a slightly greater amount of gas than the organism found 
on the shrimp. 
“Feedy”’ fish, in so far as its influence on the aes of the sardines 
is concerned, is perhaps the most troublesome factor in the sardine 
industry. Fish more or less gorged with food deteriorate very 
rapidly when taken from the water, while those having their digestive 
tracts free from food remain in good condition for a comparatively 
long time thereafter. As decomposition progresses the thin belly 
portion of the fish gradully sloughs away, producing the characteristic 
ragged appearance termed ‘“‘belly blown.” The rate of deterioration 
depends upon the quantity of and the stage of digestion of the food 
material contained in the digestive tract, and the bacteria accom- 
panying it. Feed recently eaten appears to cause a greater degree 
of deterioration than that which has been partially digested. Bac- 
teriological studies have shown that the stomach portions of the 
digestive tract are sterile when free from feed, even when digestion 
in the intestines is incomplete. By the time feedy fish reach the 
cannery they have deteriorated to such an extent and are so badly 
broken that a large percentage is entirely unfit for packing. 
In the French sardine industry(27), where bait is employed in 
catching the fish, the strictest attention is given to the quality of 
the bait in order to avoid decomposition in the fish. As late as 1853 
the use of a prepared bait containing especially powdered prawn and 
shrimp was forbidden by royal decree, as it was held that it spoiled 
the fish by facilitating decomposition. In this connection it is inter- 
esting to note that the bacteria found associated with the feed (p. 24) 
were capable of decomposing fish tissue. One of these organisms 
forms spores which resist drying but are capable of growth and 
reproduction when conditions again become favorable. The bait 
mentioned, prepared from dried shrimp, doubtless contained the 
1Tdentification of specimens made by the Division of Marine Invertebrates of the U. S. National 
Museum. 
