In this paper, the author analysed both the record of fish finder and the data of catch attained at the same time by a sardine purse seine boat operated in Tokyo Bay during 1950-1957, and the following results are obtained;
1) The depth of water where anchovy shoals swim tends to change with hour of a day, becoming rather shallow in the morning and in the evening as compared with in the daytime.
2) The depth of anchovy shoals in the water differs depending on fishing ground and weather but does not vary with size of fish and seasons.

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It is a notable character of anchovy to swim forming a shoal, the members of which sometimes jumping out of the water and another time rippling the water surface.
The one shoal in which fish are jumping is called as “Hane Iwasi” by the fisherman in Tokyo Bay and the other with rippling as “Seri Iwasi”.
The present paper describes about the conditons leading to these interesting features and also about the peculiar construction of the anchovy shoals in which fish are jumping or marking ripples.
The data used here were collected from a sardine purse seine boat which was operated in Tokyo Bay during 1950-1957.
In this treatment the authors employ the following notations for these anchovy shoals:
The shoal in which fish are jumping-Sj
The shoal in which fish are causing rippling-Sr

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Changes noticeable in a whole year in the fishing condition (rate-of-catch) and the bodylength formation (body-length frequency) of swordfish, Xiphias gladius, inhabiting in the northwestern part of the Pacific Ocean. The author has made a study by means of summarizing by month the rate-of-catch (the fishing condition) and the body-length frequency (the bodylength formation) have been determined by Kanagawa Prefectural Fisheries Experimental Station for each month for series of years with no regard to any particular year so as to minimize errors happening due to comparative scarcity of data. In so doing, also, he has avoided inclusion of data obtained from other sources than longline in order to eliminate any error arising from use of any differect type of fishing gear. From the study with such precautions the following presumptions have been obtained:
1) The area where swordfish live chiefly in the northwestern part of the Pacific Ocean is defined by Lat. 20°-45°N, Long. 140°-180°E.
2) Fishing condition of this species in a whole year in each of the sub-area within the zone above-mentioned changes in such a manner as is shown in Figs. 4 and 5.
3) The mean body-length of the species in each of the sub-area exhibits such a change as is shown in Figs. 4 and 5 while the body-length formation displays such a change as is shown in Figs. 7 and 8.
4) Swordfish in the area are generally distributed and migrate in such a manner as is shown in Fig. 6.
5) Swordfish in the area may be divided into 4 body-length groups and fish of each group are distributed and migrate in such a manner as is shown in Fig. 9, A-D.
6) High rate-of-catch of this species in sub-areas A-E and G is brought by migration of medium-, and large-sized, fish groups. High fishing rate of this species occurring in January of every year in sub-areas H and I of a young fish group together with a small-sized one and that occurring in May and June in the same sub-areas of medium- and large-sized, one.
7) Recruitment of the small-sized fish group into the medium-sized one is made chiefly in the sub-area F but it also takes place in sub-areas E, H and I.

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The studies of the individual environmental factor affecting the growth of Porphyra were carried out under the indoor culture condition suitable for the growth of Porphyra.
The results obtained are summarized as follows:
(1) The cell division of Porphyra was activated with the decrease of light intensity from 10, 000 lux to 6, 000 lux irradiation, and from 6, 000 lux to 1, 000 the cell division occurred with almost the same rate. The cell size became smaller with the decrease of light intensity.
(2) The growth of Porphyra-frond was most rapid under 6, 000 lux irradiation.
(3) The cell division of Porphyra was activated and the cell size became smaller with the drop of water-temperature from 20°C. to 10°C.
(4) The growth of Porphyra-frond was most rapid at 15°C.
(5) The color of Porphyra-frond was remarkably affected by light intensity and watertemperature.

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As often reported, if limited quantities of water and gelatin xerogel are brought into contact with each other there takes place a contraction in total volume. As to the dependence of this shrinkage on the pH value of the liquid that surrounds the gel, however, a group of investigators have found that the volume decrease attains to a maximum in a pH region about the isoelectric point of the gelatin, while another group say that it becomes minimal there; but any convincing theory seems to have not yet been put forward to resolve this antinomy.
The present author, intending to find a clue to the molecular events inducing the spontaneous wetting of extremely fresh fillet, examined as preliminaries the said contraction of a gelatin-water system and found that the contraction minimum in the isoelectric zone is just realized only at a lower temperature. He proposes, hereupon, a view that the apparent volume reduction may be caused by the resultant of two separate mechanisms, viz., (1) fixing of water molecules around rather stationary polar groups of gelatin, which reduces the space thermally swept by these molecules, and (2) migration of water molecules into oil-repellent gaps in the xerogel, which lessens the water remaining outside the gel. Results of the present experiment, in which the contraction dependence on pH of the immersion liquid was examined at different temperatures and with varying moisture-contents of sample, will serve by the help of this view to settle the pending antinomy about the contraction of a gelatin-water system.

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1) A simplified method for estimating volatile carbonyl compounds (VC) in fish is presented. This method proved to show good results in the recoveries of VC added on the one hand to fish flesh and to its steam-distillate on the other.
2) A modified procedure for the paper chromatographic analysis of VC, by which lower VC were found to be easily identified, is presented.
3) In fresh fish, VC were very small in amount. Their contents increased with the length of storage-time, and tended to decrease in the stage of advanced spoilage. The rate of VC formation varied according to the difference of state of flesh stored and also with varying parts of fish (Fig. 1).
4) By the modified paper chromatographic method, the formation of acetaldehyde, butylaldehyde and acetoin in fish flesh during storage was revealed (Table 5).

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1) By a short-time steam-heating, no appreciable amount of formaldehyde (FA) was produced from fish flesh, but by heating under pressure, it was produced to a measurable extent together with a considerable amount of dimethylamine (DMA). The amount of DMA thus produced was almost proportional to trimethylamine oxide (TMAO) contents in the flesh, whereas that of FA was not so (Table 1).
2) Thermal breakdown of TMAO was accelerated by the presence of fish extracts or certain kinds of amino acids (Table 2). The degree of decomposition of TMAO in the presence of cysteine was proportional to the concentrations of TMAO and cystein (Table 3). Quantitative ratio between these two decomposition products, however, was not theoretical in any case of experiments, which might be attributed to the some subordinate reaction of FA with certain kinds of amino acids (Table 4).
3) In several marine canned foods, content of FA was much less than that of DMA (Table 5).

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In the previous papers, authors examined bacteriostatic effects of some antiseptics on causative microörganisms of agar spoilage, inhibitory effects of these agents on bacterial agarase, and effects of sterilizing the reed mats used in drying process of agar manufacturing.
In succession to these studies, antiseptic treatments were examined of their contribution to protecting the agar from undergoing spoilage in manufacturing. The results obtained are as follows:
(1) Among antiseptics added to an intermediate product, “tokoroten”, hydrogen peroxide and chlorotetracycline were fairly effective for checking the agar spoilage.
(2) The antiseptic effects were exalted by soaking the reed mats in sodium hypochlorite solution.

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1. The presence of dimethyl sulfide, which was found to be present in the volatile component of Ulva pertusa⁵⁾, Enteromorpha sp.¹¹⁾, and in Codium¹²⁾, was not detected but the presence of methanethiol, whose presence in Digenoa simplex had been established⁴, was demonstrated.
2. As volatile components of Laminaria several compounds were isolated such as methanethiol, trimethylamine, acetone, propionaldehyde; amine I (picrate, m.p. 196-198°; picrolonate m.p. 209-210°C.), amine II (picrate, m.p. 188-189°C.; picrolonate, m.p. 192-193°), formic, acetic, propionic, butyric valeric, caproic, capric, palmitic acids, p-cresol, benzaldehyde, valeraldehyde, α-methylfurfural, furfural, and a carbonyl compound which formes a 2, 4-dinitrophenylhydrazone of m.p. 203-204°C.
3. The aroma-giving components of Laminaria sp. are benzaldehyde, valeraldehyde, α-methylfurfural, furfural, a carbonyl compound which forms a 2, 4-dinitro-phenylhydrazone of m.p. 203-204°C., and terpenes (α-pinene, d-limonene, linalool and geraniol¹⁰⁾). It was found that the characteristic aroma of Laminaria sp. can be artificially made for the first time when these aromatic components are mixed with a small amount of the odorous components of Laminaria sp., such as methane-thiol, trimethylamine, amines I and II in the condensed phase, lower fatty acids, and unsaturated fatty acids.
The author expresses his deep gratitude to Prof. Tomiyama of the University of Kyushu for his kind guidance throughout the course of this work. A part of the expenses for this work was defrayed by a Grant in Aid for Scientific Research for 1957 from the Ministry of Education which is gratefully acknowledged.

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1) The actomyosin preparation of squid muscle obtained with a procedure of the previous report showed, upon the addition of ATP, a viscosity change which is similar to the case with rabbit actomyosin. The viscosity fell quickly after adding ATP (viscosity response), a gradual recovery succeeding it (recovery effect). But the so-called splitting time was not found in the case of squid protein. The values of the ATP-sensitivity were of a level comparable with rabbit actomyosin.
2) If the protein solution was stored in the cold, the viscosity and the ATP-sensitivity were found to decrease.
3) The recovery effect was promoted by 0.001 ?? 0.01 M Ca ion, and inhibited by Mg ion of the same concentration.
4) It appeared that the ATP-sensitivity was depressed by Ca ion while it was enhanced by Mg ion.
5) The once-recovered viscosity was found to decrease again, if either Ca ion or Mg ion was present.
6) Probably the actomyosin preparation of squid might contain a homologue of the contractile muscle proteins, though it is not identical with actomyosin of rabbit and carp in detailed properties.
7) From comparison of actomyosin preparation with M-actomyosin obtained from aqueous extracts of squid, the identity of these proteins was suggested as far as the response to ATP and the salting-in behaviors are concerned.
The author wishes to express his gratitude to Dr. M. MIGITA for his valuable advise, to Prof. S. MIZUSRIMA and Prof. T. ANDO for their encouragement and to Miss M. AKIBA for her technical assistance.

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In the previous paper the authors have shown that shell-fish poison “Venerupin”, found in the livers of short-neck clam and oyster in Hamana Lake, when added into sea water, cannot be recovered without effecting a serious loss. In the usual course of recovery the solution is evaporated on a water-bath at 60°C. But this cannot be considered as a primary cause, for the poison has been proved to be stable against heat. Thus the authors were led to the assumption that salt might be responsible for the loss of poison. In order to ascertain this a series of experiments were carried out with the following results.
1. When the shell-fish poison was added to 1-3% NaCI solution and recovered from it, 60% of the original toxicity was lost (Table 2, A). The loss of the poison was amounted to 80%, when recovered from 30% NaCI solution (Table 2, B). On the other hand the poison was recovered without any loss from the aqueous solution (Table 2, 0).
2. After the shell-fish poison was kept saturated with an excess of salt for two different periods, it was recovered by direct extraction with 99% MeOH. Thus it was avoided to evaporate up aqueous solution of the poison in the presence of NaCI. The toxicity was found to be considerably decreased even by a short contact with NaCI and the decrease became more and more pronounced on a prolonged contact (Table 3).
3. In order to avoid heating the poison in the presence of salt, the shell-fish poison was added to 5% saline solution and its toxicity was assayed without extracting the poison. No loss of the poison was observed if the poison was kept in the saline solution only for a short time, while decrease in toxicity was observed either on heating the solution at 100°C. for 30min., or on prolonged storage (over 3 days) of the solution (Table 4).
4. Salts caused loss of the poison in the following order, when it was recovered from dilute salt solutions (Table 5)
Na₂SO₄, K₂SO₄>KCl>NaCl.
5. If the poison was ground with salts, diluted with water and assayed without being extracted, salts lowered toxicity of the poison in the order
Na₂SO₄anhyd.>NaCl>K₂SO₄,
K₂SO₄ having scarcely any effect (Table 6).
6. Na₂SO₄ showed such an intense effect that a definite loss of the poison was observed by mere dissolution of the poison in 5% Na₂SO₄ solution (Table 6 note^***).
As to the reason for decrease in toxicity caused by mere dissolving the poison in a dilutesalt solution, some physiological effect of salt on mice can be left out of consideration. Because the shell-fish poison is not of an acute nature, and because it was actually proved in the cases of NaCl (Table 3) and K₂SO₄ (Table 6) that injection of the poison together with a dilute salt solution did not necessarily cause decrease in toxicity.

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In the previous paper, the authors reported the nature of softening spoilage of fish sausage as well as the characteristics of the causative microorganism which was identified as Bacillus circulans according to its morphological and physiological findings.
After a culture of Bacillus circulans and other Bacillus species was suspended in a physiological saline solution, the suspension was heated for 45 minutes at 85°C in order to kill the vegetative cell, and 0.5 cc portion of the suspension was inoculated in the fish sausage paste which was sterilized beforehand.
Then the mixture was incubated anaerobically in a jar filled with hydrogen gas.
The softening, very alike to those found in the commercial product, was also observed in culture of Bacillus circulans kept at 30° to 34°C.
Some starch granules were found crumbled down around the normal granules in microscopic examination of the softened portion, as described in the previous report.
While the case of Bacillus subtilis or Bacillus cereus, none of the softening was noticed for the samples treated in the same way.
Certain difference in the nutritional requirements or the presence of inhibitors for spore germination would be explored for these kinds of bacteria. (Table 1).
In this connection, the capability as to the digestion of starch was investigated for Bacillus circulans and other Bacilli, as shown in the Tables 2 and 3.
A liquid culture medium, containing extract of fish flesh, peptone, 1 per cent of potato starch and with or without 0.5 per cent of glucose, was employed under strict anaerobic condition as mentioned above.
A remarkable increase in the activity of breaking down starch was observed rather more in aerobic culture than in anaerobic one as will be seen in Table 2.
On the contrary, for the case of Bacillus circulans, predominant consumption of starch was developed under anaerobic condition and in the medium purposely absent of the glucose as shown in Table 3.
To ascertain the extent of digestion of starch, sodium periodate was reacted to the alcoholic precipitates obtained from the culture after thrice repetition of precipitation and the amount of formic acid thus released was determined with 0.01 N NaOH solution required to titrate the acid.
Table 4 indicates that the alkali number for Bacillus circulans is much higher than those of other organisms.
Furthermore, the color intensity of iodine reaction seems to have a correlation to the amount of formic acid derived.
A clear-cut divergence in the spectrum of iodine reaction of the degraded starch was found between Bacillus circulans and other species; the absorption maximum for the former was 5800 Å and the latter 6000-6200 Å, as seen in the Table 5.
It is quite certain, from our findings that some Bacillus group is really capable to grow under anaerobic circumstance.
In 1957, Puziss, who observed the growth of Bacillus anthracis and Bacillus cereus in an anaerobic jar displaced the air with nitrogen gas, reported that these organisms readily develop both in synthetic and nonsynthetic medium containing glucose respectively.
And it is well known fact that ‘flat-sour spoilage’ or ‘off -flavor’ happened in canned foods is frequently caused by certain facultative thermophile, one of the Bacillus group.

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Canned salmon as packed in a can of electrolytic tin-plate presents an unpleasant smell though momentarily when it is opened, which is an affair not met with the case of hot dipped tin-plate can.
Supposing that at least one of the entities of the unpleasant smell may be free hydrogen sulfide gas which has been formed during the course of processing and unable to combine either with tin or with iron owing to the impermeability of the artificial resinous film coating the electrolytic tin-plate can. The authors have verified that salmon which is packed in electrolytic tin-plate can is attended by a far larger amount of free hydrogen sulfide as compared with that packed in hot dipped tin-plate can (Tables 1 and 2).

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The chlorination product prepared in carbontetrachloride can be separated more neatly by precipitation method than by evaporating off the solvent. For, when the solution is heated on a water bath, it yields a product not only dark coloured but also hardly separable from the flask. The precipitation method adopted in the present work will be summarized as follows: First of all the concentration of the product in carbontetrachloride is adjusted to 15% referring to a preliminary test made on a small fraction of the whole solution. Methanol should be ad-ded to this 15% solution till the three components (the product, methanol and carbontetrachloride) stand at equilibrium, and then the mixture is gradually poured into a weighed amount of methanol that is being stirred throughout this process. Thus the product is precipitated in the form of white powder with the yield of 90% or so. Subsequently it is air-dried. The yield does not reach 100%, since the equilibrium exists among these components.

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