a) Major wounds 



These are, as shown in Plate I, such large injuries as the loss of 

 eyes, lower jaw, opercle, or head, the breaking of the trunk, and the 

 exposure of the viscera, and almost all of the injuries of this type are 

 caused when the fish, at the time of their capture, in struggling to 

 escape crowd together at the lead line and are pinched in the net. Many 

 of these fish die immediately, but in point of numbers these are not more 

 than 1 = 2% of the fish that are capturedo When these dead fish are 

 placed in the bait well along with the other healthy bait, they putrefy 

 and pollute the water^ and for this reason they should be got rid of as 

 soon as possible 



The author gathered up from a bunch of anchovies taken for bait 

 purposes in a lift net off the Kamogawa in Chiba Prefecture on July 3, 1933, 

 all which had received major wounds in the net, and made a study of the 

 location of their wounds „ Out of 45 fish selected at random, 30 had the 

 viscera exposed by pressure on the belly, 19 had lost eyes, and 18 had 

 lost their opercles Fish with the heads missing and the trunk broken 

 were found to be comparatively few. 



No special observations were made on sardines, but in general their 

 injuries were about the same as tnose of anchovies except that it appeared 

 that a good deal fewer of them lost eyes (See Plate I) 



b) Superficial wounds 



When bait fish are carefully examined, especially those which have 

 died, the first thing that is noticed is the loss of scales, not one of 

 them having all of its scales,, Furthermore, the majority of the fish 

 show more or less bleeding at the eyes, along the belly and sides, or in 

 other places o This bleeding is liable to be wrongly considered all due to 

 simple lacerations received on the surface of the body either at the time 

 the fish were netted or when they were placed in the bait tanks. Even 

 the fishermen appear to be of this opinion, however, if these wounds are 

 carefully examined the number of simple lacerations is unexpectedly small, 

 and most of the injuries are seen to be either subcutaneous bleeding 

 caused by external damage or hemorrhage caused by the rupture of viscera. 



1) Loss of scales ' 



The loss of scales can never directly cause the death of bait fish, 

 but there is no doubt that it lowers their vitality somewhat and makes 

 them more liable to receive secondary wounds. Because of this the fisher- 

 men even estimate the vitality of bait fish by the degree of scale loss 

 among thenu The author carried out an extremely practical experiment in 

 order to find out to just what degree bait fish lose scales under any 

 given circumstances. On March 25, 1934, twenty sardines which had 

 almost all of their scales were carefully selected from a school being 



X. Poisonous matter like ptomaine appearing. 



33 



