In the Seto Inland Sea the conger eel, Astroconger myriaster (Brevoort) is a commercially important species to be caught by small sized trawlers. In the present work, growth of the fish has been studied on the basis of morphometric surveys conducted during 1952-56 for 1, 960 individuals from fishing grounds off Marugame and 1, 892 off Takuma (Table 1 and Fig. 1).
1) Frequency distribution of the anal length composition and seasonal changes in the modes (Figs. 2 and 3) have suggested that the fish under study consist of two major age groups: the young exploited during August to December and the older staying in the areas over the year. The field data indicated the average growth from summer to summer to be about 50mm.
2) Relation between total length (L) and anal length (l) of 400 specimens collected in 1956 may be expressed as
L=14.38+2.45l.
From the anal length composition obtained at Marugame during 1952-56, the mean anal length of the young and the older groups was separately computed for the coordinate months of the years (Table 3). The results revealed that the annual growth averages 50mm. in a close agreement with the one determined from the field data. However, the young group from Marugame was found a little different in the growth trend from that of Takuma (Fig. 4). The difference may be partly attributable to the particular topography of Takuma area where the tidal currents from the outer sea join each other and receed to different directions. According to the least square method, the growth of the conger eel in these areas may be formulated as follows:
For the young group occurring during August to December
l=73.143+2.150a (Marugame),
logl=1.8327+0.1288logl (Takuma);
For the older group occurring in early months of the following year
l=110.464+1.484a (Marugame),
l=105.133+1.851a (Takuma),
where l is anal length and a is age by ten day period.
3) In the conger eel under report, relation between body weight (w) and anal length (l) is indicated as in Fig. 5 and by a formula
log w=-5.8326+3.614 log l.
Assuming that the fish complete their metamorphosis in a year after hatching, it is inferable that the conger eel in the areas are composed of the two-year-old and the three-year-old groups.

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Some investigators have already reported that the ratio between the sexual and the asexual individuals, i.e. the cystocarpophytes and tetrasporophytes of Gelidium amansii, is much unbalanced on the natural rocks. From these observations they suggested that the occurrence of the alternation in generations of the life cycle of the present plant may be irregular.
According to our investigations on the individuals of the G. amansii having grown on the artificial stone-bed, it was found that the female plants (cystocarpophyte) appear in greater number than the tetrasporophytes during one or two years after settling the bed (33-100%, mean value 64%. Fig. 1 and Table 1), while later they decreased gradually to 20-35% in three or four years after settling the bed, and finally, later than four years, the ratio carposporophyte to tetrasporophyte were about 18 (4-44): 57 (19-86), nearly the same as those on the natural rocks (Tables 1 and 2).
Besides, it was also observed that among the new fronds sprouted out on the natural rocks after recovery from the “Isoyake Damage” (desert shore or burned shore) the number of cystocarpophyte and tetrasporophyte are almost equal.

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For the purpose to test its ability to stand to desiccation, the resting zoospores, the gametophytes of various growing stages, and the young sporophytes of Undaria pinnatifida were respectively exposed to the air of various humidity (45, 60.7, 84 and 100%) for various duration (15, 30, 60, 150 and 180min.) at different air temperature.
After the necessary treatment they were immersed again into the normal sea water and then cultured for two or four days when their vitality or survival rate, growth rate and condition of health were examined and estimated under microscopical observations.
The results obtained were summarized as follows:
(1) When they were well dried in the air the resting zoospores, all cells of the gametophytes and the young sporophytes were shrivelled and died with the appearance like ‘plasmolysis’ in 5 ?? 6 minutes without regard to temperature or humidity of the atmosphere.
(2) The resting zoospores were more sensitive to desiccation than gametophytes and the young sporophytes (Table 1, 2). In the case of gametophytes, those which were growing actively were more sensitive than those in resting stage (Table 3-A, B).
(3) The resting zoospores, the gametophytes and the sporophytes could alive in the air of 100% humidity for long time, but in the air of lower humidity than 70.4% the resting zoospores were fatally affected in about 30 minutes and the gametophytes and the young sporophytes were affected in respectively 1 and 3 hours (Table 1 ?? 4).
However the time which needs for desiccation of the materials varied with the temperature, that is to say, the temperature were higher, the time were shorter. Besides, the time varied whether they were cultured purely or not, i.e. it took much times when the glass slides were contaminated with other organisms such as diatoms etc.

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Sulfates of protamine type basic protein were prepared from bonito milt. The materials were purified through an activated alumina column or by 67% acetone fractionation of their picrates. A few kinds of amino acid, e. g., arginine, proline, valine, alanine, glycine, tyrosine and serine are found to be contained in the purified material through the alumina column. The molecule appears to consists of a single polypeptide chain having proline as the amino terminal residue. The molecular weight is estimated to be 5000-6000, based on the absorption spectrum of the DNP-derivative.

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Reduced viscosities, η_8p/C, of a commercial sample of agar-agar in aqueous potassium chloride were measured at 60°C. as a function of agar concentration C (g./100ml.) and KCl concentration x (moles/l.). The family of η_8p/C vs. C curves obtained for different x was essentially similar to that which had been reported for many other polyelectrolytes such as sodium carboxymethyl cellulose. From comparison with data for other typical polyelectrolytes some evidence was obtained which indicates the agar-agar molecule to have a very low charge density and a high chain stiffness.

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1. Antibacterial activity of 32 kinds of pure terpenes was examined against Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Pseudomonas aeruginose, Proteus morganii and Escherichia coli. It was thereby found that carvacrol, thymol, isoborneol, vanilline and salicylaldehyde show antibacterial activity in dilutions 2, 000 or over.
2. There was no difference in antibacterial activity according to the number of double bonds in the cyclohexane ring and introduction of a ketone radical to form cyclohexenone also had no effect on antibacterial activity.
3. Derivatives of thymol, carvacrol, eugenol, isoborneol, and vanillin, in which a hydroxyl had been introduced and directly bonded to the cyclohexane ring, showed antibacterial activity in dilutions 2, 000 or over.
4. It was presumed that addition of vanilla or eugenol as an essence to fish ham or fish sausage would be effective for the preservation of these food products.

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In the VRS determination by STROHECKER's method difficulties were experienced due to foaming in the distillation and due to tediousness in removing protein coagulum adhered to distillation flask. Data in Table 3 clearly indicate that volatile reducing substance (VRS) can be determined on an extract as well which is freed from protein by magnesium sulfate. So, the above trouble can be easily removed by employing this extract.
Since it has been found that both neutral and basic volatile reducing substances were increased at incipient spoilage (Fig. 2), the steam distillation of the extract is to be carried out in alkaline reaction (about pH 9.3). This improvement in the method gives rise to a more pronounced increase in VRS at incipient spoilage. Data illustrated in Fig. 3 demonstrate that VRS is, among several chemical indices, the most sensitive one for bacterial spoilage of the mackerel flesh.
The present method in which six-minute distillation followed by 5-minute boiling with potassium permanganate is employed, enables us to run six determinations with a single apparatus within one hour.

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For the purpose of obtaining an optimum medium for the growth of enterococci, the influences of the compositions of medium on the growth of said organisms were investigated. The enterococcal strains grew fairly well in a tryptose medium (tryptose 2%, dextrose 1.5%, NaCl 0.5%, K₂HPO₄ 0.3%, KH₂PO₄ 0.3%, pH 7.0); however, the growth of these strains were considerably suppressed in a modified medium in which “polypepton” (Daigo Co.) was used in place of tryptose. Simultaneous addition of both citrate (1% as Na-citrate•2H₂O) and 0.5% of yeast extract (or vitamin mix) to the polypepton medium remarkably enhanced the growth of enterococci, this enriched medium being superior to the tryptose medium. Although polypepton was inferior to tryptose as a source of nutrition for the growth of enterococci, it was demonstrated that said inferiority is caused mainly by the lack of some vitamins and independent of the contents of amino acid.

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The role of inosinic acid and free amino acids in make-up of the taste of Katsuwobushi stock was surveyed by sensory tests. As shown in Table 1, several kinds of test solution were prepared on the basis of the analytical values of these ingredients reported in the previous papers^{2, 3)} and tested by a panel of about twenty judges in paired comparisons. The results obtained may be summarized as follows:
The combination of inosinic acid and amino acids is judged to be more delicious than inosinic acid alone and to have a distinct meaty flavor fairly similar to that of the original stock. The amino acids, on the other hand, are almost tasteless in the concentration tested, but they clearly exert an enhancing effect on the taste of inosinic acid. The most abundant amino acid, histidine, reveals no such an effect, and the taste becomes considerably weak, if the other amino acids are omitted, though they are rather scanty in quantity. It seems probable from these results that the greater part of delicious and meaty flaver of the stock is attributed to inosinic acid, enhanced by the amino acids other than histidine.
No conclusive judgement is obtained in the comparison between histidine inosinate and sodium salt (Table 2), and this disagrees with the KODAMA's view¹⁾ that the organic salt is more delicious than the inorganic one.

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The yellowfin, Neothunnus albacora, which were caught on Indian Ocean in 1956 by a longliner, Bôchômaru, were subjected to 45- to 60-day storage in CTC-ice (about 3 to 5ppm.) aboard the boat after being dipped in or smeared with CTC-containing sea water. The freshness of fish in each group was estimated after landing by organoleptic grading and volatile bases nitrogen content of the flesh. The skin and flesh of sample fish were assayed microbiologically for CTC residue, and the flesh was also assayed for residual CTC after boiling. The results can be summarized as follows:
1. The freshness of fish after landing was the best in a group which had been iced after being either dipped in CTC (10ppm.)-sea water for 1 to 4 hours or smeared with CTC (10 and 100ppm.) -sea water. The second quality was found in a CTC-iced group without any previous treatment (Table 1).
2. When the fish one from each experimental group, was stored at 0 to 15°C after landing, the fish which was CTC-smeared and CTC-iced showed storage life of about 138% and CTC-iced fish without smearing showed that of 125% as compared with that of control fish.
3. The price of the fish which were stored in CTC-ice with and without previous chilling after being killed on the deck was exceedingly high as compared to the price of the fish which were dead when hauled and that of the fish which were left standing for one hour on the deck after being killed (Table 3).
4. The skin of fish which were smeared with CTC (100ppm.)-sea water and stored in CTC-ice for 60 days possessed 0.34mcg. CTC per g. The flesh, 1cm thick beneath the skin of the same fish, contained 0.28 to 0.59mcg. CTC per g.
5. The residual CTC in belly fillets after 3-minute boiling was found 20 to 40% of raw tissue. Negative result was obtained (lower than 0.04mcg. per g.) after 5-minute boiling (Table 4).

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The present paper deals with development of a practical fluorometric method for the determination of chlortetracycline (CTC) and with the reliability of the fluorometric method for CTC assay in ice as compared with several chemical and microbiologic assay methods.
Two field fluorometric procedures have been developed in which the visual comparison of the fluorescence of a sample with that of a standard is made by using flat-bottom test tubes, on one hand, and a portable nephelo-colorimeter, on the other, viz., (1) by the use of test tubes: place 10-cc aliquots of supernatent of a thawed sample ice and the standard CTC solution series in a series of the flat-bottom test tubes of 27mm. in diameter, and then add to each test tube lcc. of the alum reagent; after a 5- to 10-minute standing, estimate the CTC concentration of the sample by comparing from top of the tubes the intensity of fluorescence of the sample with each of the standard series while being side-irradiated with a long wave ultra-violet ray lamp, (2) by the use of the portable nephelo-colorimeter: add 1-cc. aliquot of the alum reagent to 10-cc. aliquot of supernatent of a thawed sample ice and a standard CTC solution (4 or 2mcg./cc. depending on CTC content of the sample); after allowing it to stand for 10 minutes, place the sample in one of the comparison tube, a, and the standard in the other tube, b; set the bottom of an inner tube for the tube, b, at a depth of 30mm. and by adjusting the other inner tube find the reading, h, on the tube, a, which will give fluores-cence intensity comparable to that of the standard, both tubes being equally irradiated with the long wave ultra-violet lamp; the content of CTC (mcg./cc.) can be calculated by a formula, S×30/h, where, S, the CTC concentration of the standard solution employed.
The feasibility of the fluorometric method for CTC-estimate in ice has been clearly shown by data that, while the fluorometric method gave a comparable value to that obtained by the microbiologic method, higher values were always resulted when assayed by a modified acid colorimetric⁸⁾, the UPHAM et al's⁷⁾ and the SAKAGUCHI et al's method⁹⁾, but lower values by the Japan FDA method⁶⁾.

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As previously reported^{1), 2)}, when fish fresh is treated with an aqueous solution of sodium chloride, sodium pyrophosphate or sodium tripolyphosphate, its affinity with water as reflected on the factor of water intake of the flesh attains to a minimum at a certain low concentration of the salt solution, at which it appears likely to hold between ionic characteristics of the salt and the factor of water intake of the flesh a relation independent of the kind of salt:
N•μ=0.1, 1/2∑_iV_iZ_i²×1/2∑_i|Z_i'|=0.1
wherein N stands for the factor for recalculating the molality into the normality, μ for the ionic strength at which the factor of water intake attains to a minimum, Z_i for the valency of the i-the ion and V_i for the molar concentration of the i-th ion.
Since the existence of such a minimum in hydrophilicity can constitute a technical significance for facilitating the preparation of Kamaboko of a superior quality, its validity was examined in the present work by testing the said relation in respect of its applicability to the cases of
i) salts comprising a monovalent cation and a monovalent anion: KCl, LiCl, NH₄Cl, NaF, KI;
ii) salts comprising monovalent cations and a divalent anion: (NH₄)₂SO₄, Na₂SO₄;
iii) salts comprising a divalent cation and monovalent anions: CaCl₂, BaCl₂, MgCl₂;
iv) a salt comprising a divalent cation and a divalent anion: MgSO₄.
The experimental results sustain that, so for as indentical specimens of fish fresh (see eel) are concerned, said relation holds safely for every one of abovementioned salts.

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In the present paper, further evidences are presented which favor the previously offered view³⁾ that the ability of water intake of a fish flesh retires to an extremity when the flesh is brought into contact with a salt solution of a certain definite ionic condition irrespective of the kind of salt which constitutes the solution. Using a flesh of sea-eel previously washed with water, the factor of water intake was determined for dilute salt solutions varied in concentration. The salts examined were sodium acetate, sodium oxalate and ammonium oxalate as examples of salt of organic acid, sodium bicarbonate and potassium monohydrogen phosphate, as examples of acid salt sodium pyrophosphate and sodium tripolyphosphate as examples of such acids as capable of liberating polyvalent anions.
The results of the present experiment may be summarized as follows:
i) The ability of water intake of fish flesh previously washed with water is depressed down to a minimum when the flesh is brought into contact with a dilute solution of any kind of salt examined, which satisfies a definite ionic condition. Thus, for a salt that undergoes m staged dissociations, the fish flesh is possible to form m numbering valleys of water intake.
So far as salts consisting of ions of strong acid and base are concerned, attainment of a minimum of water intake is realized when ionic concentrations of the salt sodution satisfy the equation
1/2∑_iV_iZ_i²×1/2∑_i|Z_i'|=0.1
where V_i stands for molar concentration of the i-th ion, Z_i for the valency of the i-th ion set free in the solution when electrolytic dissociation of the salt has advanced to completion, while Z_i' represents the valency of the i-th ion of the salt as existing in a certain intermediate stage of dissociation as a result of hydrolysis.
In the case of a salt comprising an ion or ions of weak electrolyte, on the other hand, the relation of the above equation does not strictly hold, actual salt concentration that corresponds to a minimum of water intake shifting to a value 1.5-2 times as high as that calculated from said equation.
ii) Phosphates (ortho-, pyro- and tripoly-phosphate) behave quite uniquely with regard to their influence upon the water intake of fish flesh. For instance, any one of their phosphates at a certain low concentration strongly depresses the water intake even in the presence of NaCl or KCl at a concentration of 1/2mol. It is worthy of note that the concentrations at which a phosphate causes a fish flesh to show valleys of water intake are senstively displaced with the lapse of time during which the fish flesh washed with water is kept out of contact with the phosphate solution; such a situation has never been met with in the case of any salts other than phosphates.

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In this paper, discolouration of a colour (new coccin) added to fish sausage products was studied. Determination of degree of the discolouration was carried out according to the following procedure: The colour is extracted into an ammoniacal alcoholic solution from fish sausage, and the optical density of the extract was measured with a Beckman electrophotometer.
Then the rate of discolouration (D) is calculated as follows:
D(%)=100(E_o-E_t)/E_o
Where E_o represents the optical density of the colour solution prepared by extracting a freshly manufactured fish sausage, and E_t that of the colour solution from a fish sausage stored for t days.
The condition of extracting food colour from the sausage and the experimental error in optical density of this method were examined. The result indicates that food colour in quantitatively extracted from a fish sausages within an error smaller than 6%, although different individuals of identical products do not always lead to an identical result.
Employing this method, discolouration of the food colour as added to 11 kinds of fish sausage products was followed up. Said 11 kinds of fish sausages were as follows: The sausages made from the white flesh of fish and the reddish flesh, some being added and the others not added with phosphates, and the fish sausages mixed with drained bean-curd up to 20 and 40%, respectively. The relation between the discolouration and the putrefaction was also observed. The results may be outlined as follows:
1) The food colour “new coccin” which was added to fish sausages gradualy discolours with the lapse of time after the completion of manufacture. In the case of fish sausage products which are at the threshold of putrefaction, the degree of discolouration is about 20%. Afterwards, however, the discolouration in suddenly accelerated with the advance of putrefaction. This result suggests that discolouration of fish sausage products can be attributed chiefly to the propagation of bacteria.
2) Addition of nitrite accelerates the discolouration of new coccin. Contrary to the general conception that fish sausages made from reddish flesh are more liable to be discoloured in comparison with those made from white flesh, the present experimental result indicates that if the customary nitrite treatment is omitted, the degree of discolouration will remain distinctly less in sausages made from reddish flesh than in those from white flesh. This suggests that, in the case of sausages made from reddish flesh of fish, the nitrite, be effective in stabilizing the myoglobin as it may, undesirably accelerates the discolouration of the food colour added to these products.

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