Report of the commissioner for 1878 : part VI.

  • United States Fish Commission
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: Report of the commissioner for 1878 : part VI. Source: Wellcome Collection.

    1150/1174 page 970
    it closely related to Clathrocystis ceruginosa, a common species growing in fresli-water ponds, which has lately come into public notice in conse- quence of the so-called pig-pen odor which it exhales when decaying. The Clathrocystis in question belongs to the lowest group of plants, the Schizophytce, many of which are the cause of decomposition or putre- faction of different animal and vegetable substances. Clathrocystis roseo-persicina is very widely diffused, being known both in Europe and America. It is found in summer along our shores, and at times is so abundant as to cover the ground with a purplish tinge, as one may see in the marshes near Lynn. It is also known in dissecting-rooms, where it grows in tubs in which bones are macerating. Wherever found it does not flourish nor increase rapidly at a temperature below 65° Falir. The next point to be considered is the manner in which the Clathro- cystis is communicated to the fish. An examination of several different packing-houses and the wharves on which the fish are landed showed that the Clathrocystis was present in large quantities on the wood-work of all kinds; on walls, floors, and the flakes on which the fish are laid. How it might have been originally introduced into the build- ings is a question easily answered when we consider how abundant the plant is on the marshes in the vicinity of Gloucester. It might have been brought in on the boots of fishermen, on sea-weed, on grass, or in other evident ways. Once in the buildings it would grow and increase on the damp wood-work, which contains usually more or less animal matter coming from the fish in process of drying. Why the plant is found at times on board the fishing-vessels themselves admits of expla- nation in two ways. It will easily be seen that, when it is common in and around the buildings on the wharves, it would be carried on the feet of fishermen on board the vessels. But there is also another reason why it should be found on the vessels. Large quantities of salt are of course used in packing the fish in the hold of the vessels. The two kinds of salt most commonly used by the fishermen of Gloucester are the Cadiz and the Trapani. I procured specimens of both kinds and submitted them to microscopic analysis. The Cadiz salt has a slight rose-colored tinge; the Trapani is nearly a pure white. The microscope shows that the reddish color of the Cadiz salt is owing to the presence in considerable quantities of precisely the same minute plant which is found in the red fish. The Trapani is a much purer salt and the Clathrocystis, if it is found in it at all, exists in very smal quantities. What must happen then is plain. The Cadiz salt, as i comes into the hands of fishermen, is already impregnated with a cot siderable quantity of the Clathrocystis. It is sprinkled in large qua] tities upon the fish as the3r are packed in the hold of the vessel, and the weather is warm enough for the favorable growth of the plat which, fortunately for the fishermen, is not the case in this latitu except for a short period, the fish must inevitably be affected durij the voyage. As soon as the fish are landed, the circumstances £
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