In judging the age of a fish, it has been customary to resort to the frequency of those rings among many individuals of the fish which are intuitively chosen as annual ring from the rings observed on the scale, the vertebra or otolith. Consequently, this has necessarily led to results not free from personal errors.
The author, now recording the frequency of any rings detectable at all on the scale for uniformly sized individuals of a fish to be examined, tries to estaflish a standard procedure for objectively estimating the age of the fish. By means of this new design it was revealed that with Euthyopteroma virgatum (H.) the chance of ring formation is provided in two seasons every year [while most individuals of this fish form (only two) rings per year.].

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It is frequently observed that the rough touch appearance develop on the surface of shell in which the filaments thrive during the long cultivation of Conchocelis. This phenomenon is called often “Samehada (Goose-skin-like) disease”. Results observed are summarized as follows:
1. The profile view of rough touch surface shows that such portion of surface consists of numerous hemispheric projections having cocentric circle lines in section (Plate I, A-H).
2. These projections are supposed to be composed of some calcium salt. 3. It seems that filaments-like passages pierce these projections and have outlets on those surfaces (Plate I, A-H). 4. No remarkable difference is observed between both rough surfaces of oyster shell (Plate I, G.H) and of pearl oyster shell (Plate I, A-F) in structure. 5. Crystals of some calcium salt are also deposited on the bottom of culture vessel during long cultivation (Plate II, A•B).

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Ohara and Katagai are famous as the bases for sardine purse seine fishery on the east coast of Chiba prefecture, but they are mutually different in that while the former is favoured by the facility of fishing harbour, the latter is not so because of the shallowness of the adjacent water up to a great distance away from the shore.
This report exermienes as to whether there can be found any difference in fishery achivement which has arisen certainly from the presence or absence of available fishing harbour, on the basis of the data supplied by the fishery associations of Ohara and Katagai.
1) The fishing fleet from Ohara is able to go fishing about 3 days more per month than the fleet of Katagai and this may be accounted for by the fact that Ohara only is furnishedwith fishing harbour.
2) From 1955 to 1957, the catch per day attained by Ohara fleet continued to be far greater than that attained by Katagai fleet. This may be due to that the tonnage of seine boats and the size of nets, which depend naturally on the presence or absence of fishing har-bour, were larger as shown in Table 1, in the case of Ohara fleet as compared with Katagai fleet.

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As a part of study on the distribution of stress on the fishing net, measurement of tensions which appear throughout the net when a statical load is imposed on was carried out.
The results obtained were as follows:
1) When a load is imposed on a knot of the net vertically, the shape of tension distribution becomes rhombic as shown in Fig. 1 (A-M). Now, if the tension which appears on the leg line starting directly from the point loaded is denoted by T, the following equation will be hold,
T/W=K_t+K_aexp(-k(n-1)) where K_t=t/W, K_a=a/W; t is the remained tension approached to a constant value by attenuation, a is the tension of the first leg minus t, k is the attenuation coefficient, W is the load imposed on, and n is the number of legs from the point loaded.
2) When a load is imposed on a knot of the net horizontally the shape of tension distribution becomes as shown in Fig. 2 (N-S). The same equation as the above will be applicable.

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The production of fish cakes in Kagawa Prefecture has been supported in respect of the raw material almost exclusively by fishes caught by trawling on the Northeastern China Sea. Therefore, the manufacturers concerned are usually obliged to use a raw fish rather degraded in freshness, which is necessarily apt to result in a short keeping of the product especially in summer. Their occasional use of boric acid and the like as the last resort for elongating the storage life of their elaborations gets often into trouble, because our food sanitation law prohibits the use of said chemicals as a preservative of food.
To save these difficulties, the authors examined the availability of sorbic acid, nitrofurazone and nitrofurylacrylamide for protecting fish cakes from readily undergoing putrefaction. Organoleptic and bacteriological examinations made on three types of fish cake which had been prepared from batches of raw flesh added with said chemicals, either separately or in combination, and exposed after their preparation to temperatures between 25.5° and 32.2°C and relative humidities between 80 and 91% presented the following results:
1. Preservabilities of Tempura and Chikuwa can be little improved by the presence of 1% soribic acid together with N.F. (a mixture containing 3-(5-nitrofuryl) acrylamide and nitrofurazone in a ratio of 4: 1) at an amount less than 0.0005%. But the storage lives of these fish cakes can be distinctly lengthened by the presence of 0.001-0.002% N. F. added to raw flesh, and it is further elongated by additional presence of 1% sorbic acid even to such an extent as unattainable by singular uses of these chemicals at said concentrations.
2. When applied to Kamaboko, N. F. exhibits a preservative effect which lasts over 40 hours to be almost 40 times as strong as that of sorbic acid.
3. Singular application of N.F. at concentrations lower than 0.002% brings about no favorable effect on the preservation of Tempura and Chikuwa.

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In the previous papers^{l, 2, 3)}, characteristics of the softening spoilage of fish sausage, species of causative bacteria with reference to its activity of decomposing starch under anaerobic condition have been reported. In addition, the use ⁴⁾ of a mixture of three different compounds, including sodium pyrophosphate, sorbic aicd and glucose was suggested to be effective as apreventive means of this particular spoilage.
This time, the nature of sodium pyrophosphate relevant to the retardation of growth in the spoilage bacteria will be discussed.
W. Vishniac (1950)¹⁸⁾, and separately G. Dirheimer (1956)¹⁹⁾, already pointed out an inhibitory effect of pyrophosphate or tripolyphosphate on yeast hexokinase. They noticed that some chelating action of these polyphosphates with magnesium ion would cause the inhibition of hexokinase, which then can be restored by addition of MgSO₄ or adenosinetriphosphate.
Halvorson (1957)⁵⁾ stated that certain bacterial spores will be able to make process of glucose metabolism without E. M. P. glycolytic cycle. After the germination take plack, however, phosphorylation reatcion²²⁾ should be necessary for normal growth and propagation of their vegetative cells. It is probably valid from Treadwell's experiment (1958), in which headded one of the following sodium azide, monoiodoacetic acid and dinitrophenol to the spore culture and found a marked retardation in growth phase of vegetative cells after the germination had completed.
A similar line of the research is just our primary concern about Bacillus circulans how the different stage of its growth is really inhibited by the presence of sodium pyrophosphate and sorbic acid.
By a test for the culture of Bacillus circulans in a medium containing pepton, glucose, sodium chloride, and sodium pyrophosphate (0.4 per cent), it showed a more restricted consumption of glucose accompanied by a samll change in pH value throughout the cultiion than the culture in which the polyphosphate was entirely absent.
A nepherometric observation was carried out of the whole progress of growth, covering germination, outgrowth and cell division of the microorganism, with a culture medium, to which L-alanine (6mM), adenosine (12 μM), sodium pyrophosphate (0.4%) and sorbic acid (0.1%) were incorporated. As shown in Fig. 3 and 4, the pyrophosphate not looks like to affect on germination but on the growth phase afterward. Also it is clear in a series of photomicrograph of Plate 1, vegetative cells in chain form can scarcely be seen even after 24 hours' incubation, while in a control run, many rod-shaped forms in chain are found in a sample of 9 and 24 hours'. The presence of sodium azide or monoindoacetic acid can give a similar pattern of growth (Plate 2 and 3). Also electronmicrographs from Plate 5, 6 and 7 would show a moredetailed picture of each growth phase. In the culture containing sodium pyrophosphate, certain number of spore indicate translucnt area in spore and others are partly broken after a few hour's cultivation and small number of vegetative form only develops in 24 hours' culture.
From the foregoing findings, sodium pyrophosphate and sorbic acid seem to play a main part of inhibition on both growth phase and cell division rather than on germination of the spores of Bacillus circulans.

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Having collected forty-nine kinds (35 fish sausages and 14 fish hams) of fish sausage manufactured by various makers, the author has examined the number of bacteria present in content of the sausage. Aerobes and anaerobes are examined in their counts before and after samples have been kept at a temperature of 30°C for some two weeks.
The results obtained are shown in Table 1 and Figs. 1-4.
In all the samples bacteria are found to exist more or less. Before the samples have been kept at the temperature, the number of anaerobes present in the meat is generally less than that of aerobes. In other word, most (ca. 80%) of the samples contain 10²-10³ of aerobes and 10¹-10² of anaerobes per g. of the meat. But after the samples have been kept at the same temperature for the same duration of time, bacteria in all the samples increase in number, though their increasing degree vary with the kinds of samples. In sixteen samples of ours the contents fo aerobes are found to be more than 10⁶ per g. of the meat, while in the fifteen samples those of anaerobes are also more than 10⁶. Some of samples are organoleptically observed to have been deteriorated during their storage. But the deterioration degree dose not seem to correlate with the number of bacteria present or grown in the meat.
It seems clear from Fig. 4 that the environmental conditions of fish sausage to be caused by its casing are generally neither aerobic nor anaerobic enough to inhibit the growth of aerobes or anaerobes.

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The present study is intended to ascertain how the kinds of bacteria in the meat of fish sausage act upon its spoilage. All the aerobic strains that have been isolated from the samples used in the previous work¹⁾ we have classified into three kinds-spore forming rod, non spore forming rod and cocci. Together with these, those which have been isolated from the samples, when kept at 30°C about two weeks, are brought about to the identification by BERGEY's manual. Some of the strains identified are tested respecting the formation of volatile base and histamine.
The results obtained are shown in Table 1 and Fig. 1, which may be summarized as follows:
1) Spore forming rods are found predominant in all the samples, but non-spore forming rods and cocci are found only in about one-third of all the samples.
2) Between the bacterial flora isolated from the deteriorated samples and that from those samples where no deterioration is recognized in spite of the increase of bacterial counts, there is a remarkable difference. Isolated from the former are Bac. subtilis, Bac. pumilus and Sarcina flava, while isolated from the latter are Bac.coagulans, Bac. firmus, Bac. lentus, Bac. circulars, Bac.michaelisii, Bac.kaustophilus and Flavo. invisibile.
3) Remarkable activity of forming volatile base is observed among Bac. subtilis, Bac. pumilus and Sarcina flava, which have been principally isolated from the deteriorated samples of ours, but it is not so with the other bacteria. Any of those examined strains can hardly produce histamine.

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In the previous works^{1), 2)} it has been reported that plenty of aerobic bacteria belonging to genus Bacillus are present in fish sausage and that fish sausage is in so anaerobic a condition as can hardly inhibit the growth of Bacillus. In tne present work the growth of those three kinds Bacillus, namely Bac.subtilis, Bac. coagulans and Bac. firmus, which have been isolated from fish sausage is studied under aerobic and anaerobic conditions, and at the same time are measured changes of the Eh of the media to be caused during their growth. Each of the Bacillus used for the purpose is cultured under three different conditions-aerated, aerobic stationary and anaerobic. The anaerobic culture is made by means of ROSENTHAL method. For the aerobic cultures, both methods aerated and stationry are used in order to vary the amount of oxygen to be put into the media, either method being usually taken for the purpose.
The results obtained are shown in Tables 1-3 and Figs. 1-3, which may be summarized as follows:
All the used bacteria can grow well in the aerobic conditions, though their growth is predominant in the aerated culture, but less so in the stationary one. The germination of spores takes place in Bac. subtilis and Bac. coagulans either in the aerobic or anaerobic condition, but Bac. firmus hardly germinates spores in the anaerobic condition. In the anaerobic condition Bac. subtilis seems to be able to grow vegetatively to some extent, though its sporulation seems difficult in it. As for Bac. coagulans, no such thing occurs.
As Bac. subtilis grows, the Eh value of the medium is lowered in the aerobic culture, but raised in the anaerobic one, consequently some definite range (-100 ?? -150m volt) is reached regardless of the cultural method to be used. As Bac. coagulans grows, the Eh value of the medium is lowered to be raised again. When Bac. firmus begins to grow, the Eh value is unchanged, but when it has reached the maximum of its growth, the Eh value is lowered to some definite degree. As to latter two kinds of bacteria, the Eh value in the aerated culture is always higher than that in the aerobic stationary culture, and these values are not lowered into minus range throughout their growing period.

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Cytochrome c (Cyt) was purified from a red alga, Porphyra tenera, by the procedure shown in Fig. 1. This preparation containing 0.474% iron proved to be homogeneous electrophoretically at various pH's. The visible absorption spectra of this Cyt showed remarkable characteristics, especially in reduced form: in 0.1M acetate buffer of pH 6.0, the extinction coefficient of α maximum (at 553 mμ) was found to be only about 3/4 of that of vertebrate¹¹⁾, in addition to that the whole spectrum shifted towards longer wavelengths than that of vertebrate as pointed out already¹⁾; in 0.2 N NaOH, the whole spectrum was found to be very similar to that of vertebrate, both in the positions and in extinction coefficients of maxima or minimum, and the extinction coefficient of α maximum was higher than that in the acetate buffer (Fig. 2 and Table 1). Such a large difference of spectrum as caused by the change in pH seems not yet to have been reported for Cyt from any source. The pH-mobility curve of this protein differed also considerably from that of horse¹⁴⁾ as shown in Fig. 3. The isoelectric point of this Cyt was found to be around pH 4, which forms a marked contrast to vertebrate Cyt (above pH 10)^{10, 14)}.

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Regarding the elongation of storage life of marine products, the authors evidenced an antioxidant (BHA) and electro-smoke solution⁸⁾ in respect of their effect of protecting salted-and-dried saurels (moisture, 68-70%) from undergoing radiation-deterioration of oil. The fish products were exposed at room temperature to a gamma ray from ⁶⁰Co (1000 curies).
The results obtained confirm that the oil oxidation caused by irradiation can be substan-tially evaded whether the antioxidant is present or not, when the products are kept packed in evacuated polyethylene bags.
Although development of the so-called radiation-odor could little be suppressed neither by addition of antioxidant nor by vacuum packing, the antioxidant did positively hinder not only the accumulation of peroxide-oxygen prior to irradiation but the oil-oxidation under radiation. The application of smoky odor of electro-smoke solution was fairly effective in neutralizing the offensive odor.

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Aboard ship immediately after catching, the saury was treated with sufficient ice containing 5 p. p. m. of CTC in such way to rinse out the surface of fish body with its melted water, transferred to the laboratory and kept with further addition of it for 17 days. Chemical and organoleptic examination for the freshness of fish was made during the period of storage and the amount of CTC penetrated in the flesh was also determined by the Tomiyama's microbio-logical assaying method using cylinder plate. The results can be summarized as follows:
(1) The quality of saury was preserved passably well in CTC-ice for 17 days, whereas in plain ice for 8 days.
(2) At the beginning stage of CTC-icing, the flesh contained about 0.02γ of CTC per gram of tissue and thereafter its content attained to 0.16-0.34γ per gram of tissue.
(3) Generally speaking, the big saury contained a larger amount of CTC than the small one and its content was lower in the dorsal and ventral part than in the caudal one.

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The purine compounds from the muscle of some fishes (mackerel, trout and rainbow trout) have been studied by the hydrochloric acid gradient-elution system on Amberlite IRA-400. By the same technique changes have also been followed in the nucleotide composition of rainbow trout muscle which was stored at an ambient temperature of about 0°C. From these studies it has been observed that in red lateral muscle, as compared with dorsal, two specificities are notable. The first is the difference in the total amounts of purine compounds especially those of inosinic acid (IMP). In red lateral muscle less amounts of the purine com-pounds are found than in dorsal muscle. The second is dependent upon the degree of splitting of IMP. In red lateral muscle there is a rapid splitting of IMP as time goes by while in dorsal the same phenomenon as in carp muscle (accumulation of IMP) is observed; as a re-sult, the amounts of inosine and hypoxanthine in the former increase rapidly. This may be due to the more strong activity of 5'-nucleotidase in the former.

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A number of studies were reported on the uptake of dissolved P³² by aquatic organisms¹⁾. The present authors demonstrated that the fresh water fish was able to uptake P³²O₄ ion directly from aquarium water and that the gills were the major pathway for its absorption²⁾. No works have been made, however, of the turnover of the directly uptaken phosphorus among various phosphorus compounds except for that in the developing sea urchin embryo^4'5) The present paper deals with the turnover of absorbed P³² in a sludge worm, Rhizodrilus limasus (HATAI).
The radioactivity of the worm increased rapidly and linearly with time of culture when this worm was placed in P³²-containing water (Fig. 1). The acid soluble fraction was pre-pared by blending a sharply frozen tissue with trichloracetic acid. The lipide-, nucleic acid-and phosphoprotein-form phosphorus were fractionated from the insoluble part by the SCHNEIDER method⁷⁾. The distribution patterns of P³² in these four fractions were studied when the worm was active in absorbing P³², on one hand, and in excreing it, on the other (Fig. 2-5). It was found that P³² which was absorbed by Rhizodrilus, entered at first into the acid soluble fraction and that the acid soluble p³² was largely incorporated in both nucleic acid and lipide whereas only slightly in protein (Fig. 6).

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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.

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