Portion Of Fish Research Articles

ねり製品の内部腐敗に関する研究-I

It has been shown in the preceding paper that interior portion of fish jelly products (Kamaboko) or fish sausage is being kept in a condition of rather low oxidation-reduction potential, Eh value likes range between -0.100 and -0.250 volts. Taking into consideration of this factor, the present report dealt with observation of the growth under different level of oxidation-reduction potential for some varieties of Bacillus group including both type strains and the organisms isolated from commercial fish sausage. In a test with glucose-agar medium, 11 strains from 21 strains of Bacillus species failed to grow where the initial Eh value was adjusted to -0.2 volt with thioglycolic acid, however, none of the strain of Bacillus megaterium tested could indicate growth. These findings were never shifted to any other pattern, even when yeast extract was added to the medium, but most strains lost ability to grow on the medium lacking glucose, while in the medium containing starch in stead of glucose, the majority of strains showed fairly good growth as in glucose-agar medium. These results suggest that Bacillus species normally need certain fermentative sugarfor their growth in low potential condition. The lowest Eh value of the glucose-agar medium which enables growth of these strictly aerobic Bacilli was found to be near +0.20 volt for both spores and vegetative forms. On the other hand, in a medium without glucose, these microorganisms required a condition in which the minimum Eh value should be kept above +0.24 volt. The growth of facultative aerobic strains, capable to grow even at low potential, was also affected by the change in oxidation-reduction potential of media. Under circumstance of high potential such as the Eh above +0.23 volt, facultative aerobes showed much vigorous development, but if the potential of medium would turn to negative region, these strains could grow only in less extent. And also, some strains of this group were no more able to grow at the Eh below -0.25 volt and in addition, the colonies formed in agar medium became to decrease in their number in accordance with reduction of the potential.

Notes on the Upper Keuper Section at Shrewley where the Fish were found, and on the Trias generally in Warwickshire

As a rule, the Trias in Great Britain, considering its extent and thickness, is noted for the paucity and rarity of fossils, perhaps it is the most unfossiliferous of all rocks containing organic remains in this country, especially when compared with the abundant fauna and flora of the New Red Sandstone in Europe and other parts of the world. Any addition therefore to our knowledge in a field so comparatively barren is of considerable interest to the Palæontologist. It is now many years ago since I discovered Palæoniscus superstes , apparently the last of the genus, in the Upper Keuper at Rowington. Last summer, in company with my son, Mr. Douglas Brodie, I visited the sandstone-quarry at Shrewley, and he drew my attention to some obscure remains on a slab of sandstone which, when cleared, turned out to be portions of fish, unfortunately fragmentary and ill preserved, belonging to the genus Semionotus , which, though frequent in the German Keuper at Coburg, Stuttgardt, and elsewhere, has not been previously recognized here. On a second visit I found a few more in a somewhat better condition, all of which I placed in Mr. Newton's hands. On the slab on which the first specimens were found were two impressions of footsteps of a large Labyrinthodon , and I fancy that the whole number, seven, may have been lying on the surface of one large slab afterwards broken on removal. The following section of the quarry will show the probable position of most of the fossils