192 FOOD POISONING. 



duce other symptoms also contain ptomains remains for future in- 

 vestigations to determine. 



In 1887, three cases of mussel poisoning, one fatal case, occurred 

 at Wilhelmshaven, the place which supplied Brieger with the mus- 

 sels from which he obtained mytilotoxin. Schmidtmann found that 

 non-poisonous mussels placed in the waters of this bay soon became 

 poisonous, and that the poisonous mussels from the bay placed in 

 the open sea soon lose their toxic properties. Linder has found in 

 the water of the bay and in the mussels living in it a great variety 

 of protozoa, amoebse, bacteria and other organisms, which are not found 

 in the water of the open sea nor in the non-poisonous mussels. He 

 also ascertained that if the water of the bay be filtered, non-poisonous 

 mussels placed in it do not become poisonous, and he concludes that 

 poisonous mussels are those which are suffering from disease due 

 to residence in filthy water. Cameron makes a somewhat similar 

 statement about the poisonous mussels near Dublin, taken from 

 water contaminated with sewage. He found that the livers of these 

 animals were much enlarged, and from them he obtained a base that 

 is probably identical with mytilotoxin. That oysters taken from 

 beds near the outlet of sewers may be contaminated with the speci- 

 fic germ of typhoid fever has been well demonstrated, within the 

 past few years, and that they may become poisonous in the same 

 way that mussels acquire harmful properties is also well known. 

 Pasquier reported cases of poisoning at Havre from the eating of 

 oysters taken from an artificial bed near the outlet of a drain from a 

 public water closet. Christison says that an unusual prevalence of 

 colic, diarrhoea and cholera at Dunkirk was believed to have been 

 traced to an importation of oysters from the Normandy coast. There 

 should be police regulations against the sale of all kinds of moUusks, 

 and all kinds of fish as well, taken from filthy water. Special at- 

 tention should be given to localities that have once supplied poison- 

 ous food of this kind. Many popular rules have been formulated 

 for the easy recognition of poisonous mussels, and to some of these 

 credence has been given by medical authors. An unusually large 

 mussel is regarded with suspicion, and Lohmeyer gives measure- 

 ments that may guide the person in search of this article of food. 

 Stress is placed on color by some, and one is advised to avoid the 

 dark brown-blue, and purchase the dark-blue or dark green-blue. 

 We may expect to see the prudent hungry man draw from his 

 pocket a scale of colors and carefully compare it with the shell of 

 the juicy bivalve before he consigns it to his digestive organs, if he 

 is to observe the rules laid down in some recent medical works. 

 Then he will take the dimensions of the whole, measure the thick- 

 ness of its shell, and then its strength, for we are informed that the 

 poisonous clam has a thin, brittle shell. Seriously, one is to avoid 

 shellfish from impure water, and he may properly insist that they 



