124 American Fisheries Society 



tode exists, and that in the course of its life history it uses 

 as its intermediate host a large number of species of fish, 

 and for its final host one or two species of shark. That 

 among its intermediate hosts the common butterfish is 

 unique in that the cysts occur not on and in the tissues of 

 the viscera but in the muscles. This objection has been suf- 

 ficiently answered in the foregoing part of this paper. It 

 now remains to instruct the public so that they may be able 

 to use a valuable food fish without offending the most exact- 

 ing demands for uncontaminated food and at the same time 

 to show the true position which these humble forms occupy 

 in the animal kingdom. I find from conversation with one 

 who has seen a badly parasitized butterfish, but whose zoolo- 

 gical education is that of the average citizen, that his line of 

 thought is somewhat as follows: "The demonstrator 

 showed me a fish whose flesh along the back-bone was full 

 of little yellowish bodies that looked like fine fish roe. He 

 said they were worms. Now you don't catch me eating 

 wormy fish." In other words, the unfortunate word worm 

 calls up visions of putrefying meat which should not be 

 suggested by cysts in the flesh. I have examined large 

 numbers of butterfish which have had these cysts in the 

 flesh, but have never seen any signs of inflammation or of 

 bacterial infection resulting from their presence. I there- 

 fore feel justified in saying that these encysted larvae not 

 only look like fish roe, but that their nutritive value cannot 

 be much less than so much fish roe ; that there is no evidence 

 of any condition to suggest danger from ptomain poisoning; 

 and that, therefore, there should be no hesitation about 

 using butterfish as food. If one's imagination suggests un- 

 pleasant associations he may find relief in the thought that 

 all the cysts in ordinary cases of even badly infested fish 

 will be removed by the cutting out of the back-bone and its 

 accompanying spines, between which the cysts occur. 



At the risk of repeating what has already been said, the 

 importance of the case demands that it be stated explicitly 



