20 POISONOUS MOLLUSCA. 



Mussel (Mytilus edulis) is that which proves most frequently 

 poisonous. I have known them to produce an itchy eruption 

 and swelling over the whole body, attended with great an- 

 xiety and considerable fever. " On some parts of the coast 

 of Yorkshire, where mussels are abundant, a belief is preva- 

 lent among the people that they are poisonous, and they are 

 consequently never eaten."* Many cases are on record in 

 which their use has proved fatal. A case, says Dr. Bateman, 

 is mentioned by Ammans and Valentinus, in which a man 

 died so suddenly after eating mussels, that suspicion of hav- 

 ing administered poison fell upon his wife. Some of Captain 

 Vancouver's men having breakfasted on roasted mussels, were 

 soon after seized with a numbness about their faces and ex- 

 tremities ; their whole bodies were shortly affected in the 

 same manner, attended with sickness and giddiness, and one 

 died. Of the mussels of Van Dieman's Land, Captain Frey- 

 cinet reports that they often enclose a small crab, or little 

 greyish pearls ; such mussels ought to be avoided, since they 

 are liable to occasion severe colics, f In the month of June, 

 1827, a great number of the poor in Leith were poisoned by 

 eating these shell-fish, which they procured from the docks. 

 " The town," says Dr. Combe, " was in a ferment, and the 

 magistrates, with great propriety, issued a warning against 

 the use of the mussels. Many deaths were reported, and 

 hundreds of individuals were stated to be suffering under it. 

 Luckily matters were not so deplorable ; but we ascertained 

 that, in addition to the man mentioned before, the companion 

 of our patient, an elderly woman, had died. In all, about 

 thirty cases occurred, with great uniformity of symptoms, 

 but varying very much in severity : but none, so far as I 

 know, have left any permanent bad effects.";}: To what 

 cause these deleterious effects are to be ascribed is uncertain ; 

 for mussels, you are aware, may commonly be eaten with 

 impunity. The common people attribute all the symptoms 

 to the person having unwarily swallowed the beard or byssus 

 of the fish, but there is no doubt that the opinion is erro- 

 neous. Some of the learned ascribe them to the presence of 

 parasitical worms, to the spawn of star -fish, or to microsco- 

 pical medusae ; others, to the mussel having fed on some 

 poisonous articles, more particularly on the ores of copper ; 

 others believe the mussels to be in a diseased condition, or in 

 a state of putrefaction ; and others refer all to the peculiar 



* Bateman on CvTt. Diseases, 89. 

 t Voy. anx Terrcs Aiist. 43. 



X Edin. Med. Snrg. Journ. xxix. 88. See also the Med. Quart. Review, 

 iii. 179 ; and Christison on Poisons, 462 — 8. 



