ICHTHYOTOXISMUS. 197 



these belong to the family of Scombridse. This is in accordance 

 with the observations of Gubarew, who has reported cases of poison- 

 ing from eating Scombrida saba. However, the etiological relation 

 of these fish to kakkg cannot be said to be positively established, and 

 it is true that in some parts of the world certain species of the Scom- 

 bridse are eaten without injurious effects. Nothing definite is known 

 about the nature of the poison of these fish, nor has it been deter- 

 mined whether the active agent is a physiological product of certain 

 glands or a result of bacterial activity. 



Petromyzon fluviatilis, which is not classed among fish by modern 

 zoologists, causes, according to Prochorow, a bloody diarrhea, fre- 

 quently observed in the Jamberg district of Russia. This occurs 

 whether the animal is eaten raw or thoroughly cooked, and it is 

 stated that if salt be sprinkled on the animal while it is alive its 

 skin secretes an abundant discharge of mucus, and after this the 

 flesh is not poisonous. Bohm and others have expressed some doubt 

 about any species of fish being per se poisonous. They have been 

 inclined to attribute the effect so frequently observed to one or the 

 other of the following causes : (1) Meat rapidly undergoes putre- 

 factive changes and the ill effects are due to true botulism. (2) The 

 observed untoward symptoms are explainable by supposing the ex- 

 istence of a marked idiosyncrasy in the consumer. That the first 

 supposition is not true is shown by the following facts : (1) Poison- 

 ing with perfectly fresh fish occurs not only in the tropics, where 

 decomposition goes on rapidly, but in the temperate zone as well, 

 and during seasons of the year and under conditions that exclude the 

 possibility of the ill effects being due to putrefactive changes in the 

 meat. (2) Certain species of tetrodon and other fish are so well 

 known to be poisonous, even when perfectly fresh, that their con- 

 sumption is at times resorted to, notably in China and Japan, for 

 suicidal purposes. ' That the symptoms are not due to idiosyncrasy 

 in the consumer is demonstrated by the effects of the flesh and of 

 the expressed juice upon the lower animals. 



3. Cluppea thrissa and C. venenosa, also certain species of Scarus, 

 have no poisonous glands, nor are their reproductive organs more 

 poisonous than other parts of the body ; still the flesh of these fish is 

 always poisonous. According to Gunther, their harmful properties 

 are due to the medusae, corals, and other decomposing substances 

 upon which they feed. In the West Indies it is a well-known fact 

 that all the fish caught off certain coral banks are poisonous and that 

 every part of the animal is unfit for food. The symptoms are those 

 of a gastroenteritis, and death frequently results. 



It has been suggested that ichthyotoxismus may be due to substances 

 of vegetable origin which are employed in some countries, notably 

 by savage and partly civilized peoples, to kill the fish. That this 

 may be true in some instances is possible, but that this explanation 



