During an experiment which has been carried out to analyse the influence of chlorinity on the blood elements of a species of rockfish, Sebastiscus marmoratus, some specimens kept in the experimental tanks have incidentally developed ulcers. Examinations of the blood elements were therefore carried out in order to compare the amount of each constituent under normal and diseased conditions.
Four male fish were used as the materials in the present study. The sampling dates of the fish and the experimental conditions are shown in Table 1. The sequential changes of water temperature and chlorinity in the experimental tanks are also indicated in Figs. 1-3. Determinations of the amount of moisture content of the blood, specific gravity of the blood, serum protein, erythrocyte, chlorinity and hydrogen ion concentration were all made using the same techniques employed in the previous study⁷⁾. Blood was also drawn from the specimens in the same procedure as in the previous investigation, and the same foods were also given. To determine the haematocrit value, a small amount of blood was filled in a capillary (1.25-1.50×75mm) heparinized previously with heparin to prevent blood coagulation. A high speed centrifuge for haematocrit measurement was then applied for ten minutes at a speed of 10, 000 rpm. A capillary itself was then put on a haematocrit counting desk for enumeration. In measuring the urea nitrogen level of serum, 0.2ml of serum was dropped into a test tube (10×75mm) in which a piece of urea nitrogen chromatography paper (Warner-Chilcott, Co.) was inserted. Reaction was then observed after thirty minutes of treatment.
The experimental results indicated that:
1. Symptoms of ulcers appeared first on the spines and fin rays of the dorsal fin, opercula, between the pectoral and ventral fins, between the dorsal fin rays and anal fin, and on the caudal peduncle as well as the caudal fin. In these parts, the color turned into a greyish white, probably owing to the aggregation of melanin granules in melanophores. The suffering individual was likely to isolate itself from the original group and separated singly in the experimental tank. Although activities of such fish were very low, their response to a slight stimulation, sound for example, was extremely sensitive. Later the condition of the illness took a serious turn; the neural spines, caudal vertebrae and urostyles could therefore be seen from the outside as a part of the epidermis was damaged at this stage of the disease (Plate I-a, b, c). The color of the gill and Cuvierian duct turned into a yellowish orange in spite of the original color being dark red in healthy specimens.
2. When the ulcer reached a serious stage, the specific gravity of blood decreased considerably. While, the moisture content of the blood increased from 89.9% to 91.5% (Fig. 4).
3. The amounts of serum protein in the ill specimens were also a little (0.3-4.O%) less than those of normal individuals (Figs. 6 and 7).
4. Similarly, the haematocrit values decreased remarkably (8-16%) when a fish had an ulcer. In a specimen whose haematocrit value was lowered from 19.3% to 3.0%, the leucocyte concentration went up to about 2.5% which seemed to be much higher than that of normal individuals (Figs. 5 and 7).
5. The test with urea nitrogen chromatography paper gave no positive reaction on the serum of normal fish. However, a value of 10mg/100ml was obtained when the ulcer began to develop and it reached up to 40mg/100ml when the fish was seriously affected by the ulcer (Plate I-d).

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1. Amino acid composition of the extrapallial fluid which favours to occurrence of calcite shell was investigated on Chlamys nobilis and Crassostrea gigas, and results were presented together with discussion in special reference to the polymorphic formation of calcium carbonate in molluscan shells.
2. The amino acid pattern of the fluid was to differ from conchiolin in each species. It is therefore possible that parts of organic substances secreted from the mantle are abolished or changed in the process of formation of a calcitostracum as seen in the nacre.
3. The extrapallial fluid contacted with the calcitostracum or the nacre did not appear to have the amino acid pattern which is characteristic of calcitic or aragonitic conchiolin, respectively.

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1. Amino acids of the mucous substance covered on the inner surface of mantle of Pinctada martensii and Chlamys nobilis were determined by using a KLA-3 Hitachi amino acid analyzer.
2. In Pinctada martensii at least, the amino acid pattern of inner mucus where shell matters never occur in vivo did not differ from that of extrapallial fluid which is secreted on the shell side of a mantle and able to form mineralized shell.
3. The similar number of aspartic acid, serine and glycine residues which are the main amino acids of mineralized matrix were found between both the mucus of the two species, respectively.

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Sawara, Scomberomorus niphonius (CUVIER et VALENCIENNES), is a commercially and ecologically important species in the Inland Sea of Japan.
The main fishing seasons are from March to June (spawning season) and from September to November (feeding migration season). Angling and gill-net are important types of fisheries.
The present authors conducted trial fishing from 1963 to 1966 and collected specimens for studies. Juveniles (Plate 1) caught by commercial boat seine in the water off Tushi of Awaji Island in September 1966 were also used. The results are summarized as follows:
1) Correlation were calculated for some combinations of total length (T. L), fork length (F. L), head length (H. L), and otolith length (O. L).
Regression formulae in terms of g and mm are,
F. L=0.856 T. L+30.21 (Fig. 2)
B. W=8.512×10^-6×F. L^2.990 (Fig. 3)
O. L=0.0427×F. L^0.887 (Fig. 7)
H. L= 0.545×F. L^0.836 (Fig. 8)
O. L=0.0979H. L+0.32 (Fig. 9)
2) In order to locate the position of otolith, a linear relation between the length from snout to the front tip of auditory capsle (S-Ac) and the head length was applied,
(S-Ac)=0.488H. L+1.30 (Fig. 6)
3) The otolith of this species is brittle and weak. The hind part of otolith shows translucent zones and opaque zones. It was assumed that the translucent zones are winter rings (Table 3, Fig. 5 and 10 and Plate 1). Growth of fish is estimated as shown in Table 4.

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Large set nets in the coast of Gotoh Island in western part of Kyushu are constructed for catching yellow tail which migrates to this sea area in spring. The yellow tail in this season is usually called “Higan-Buri” in this province.
The net in northern coast of Gotoh Island is always settled down earlier than that of southern coast in the season. Thereby, net setting month is late as far as to south. It seems that yellow tail caught by those nets is a group which comes down south, and belongs in same party in this sea area owning to similar variation of the annual catch by those set nets.
In the annual catch of yellow tail, first class nets which catch more than others have not so fluctuation as the other one. And in the tendency of those above, better net is kept balance in the catch of them. It also shows that the migration of yellow tail to this sea area, the place of sojourn and the regular course of them toward the coast are almost fixed in same environment every year.
As mentioned above the author concludes that the catch by large set nets which belongs to the excellent group should be nothing particular variation per annum in the coast of Gotoh Island in future.

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In order to make clear the relation between the size of live bait and its activity, mortality and escape in tuna long-line fishery, a comparative test was carried out using the horse mackerels of two different sizes, larger or smaller than those of usually used bait. The methods of the test were the same as previous paper (IV).
The results are as follows.
1) The escape of large fish attains to 20% in slightly hooked bait (b), and to 14% In deeply hooked bait (b'). In the case of b, a lot of branch-lines were entangled. The mortality was only 4-2% in both cases. While in the case of small fish, the mortality and the escape of b, b' was 4% respectively. (Table 1, Fig. 1).
2) As regards the activity of live bait after eight hours on hook, b was found to be excellent than b' in the case of both the large and the small fishes.
Generally speaking, the maintenance of live bait seems to be superior in small fish than that of large fish. (Table2)

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Boiling of fish is a traditional method of preservation practiced in many countries in Southeast Asia and the Far East. A modification of the traditional method, in that the fish was wrapped in the parchment paper, was evaluated. Six different salt concentrations, namely, 5, 10, 20, 30, 40, and 50% in the proportion to the fish weight, were tested. The quality of the product was determined by chemical, microbiological, and organoleptic tests performed at weekly intervals during storage.
The amount of salt found in the product was relatively independent of the amount of salt used in the preparation. Pure salt, as used in this study, and probably heating, inhibited the development of rancidity, as judged organoleptically, and by the relatively low peroxide numbers, especially in the samples prepared with higher salt concentrations. Further investigation, however, is needed to determine the effect of sodium chloride and heat treatment on the prevention of rancidity in the boiled fish product.
The bacterial count, TVN, and TMA values increased up to two weeks of storage and decreased afterwards. Boiling alone causes the formation of ammonia and the breakdown of TMA oxide into TMA.
The organoleptic test result shows that the products prepared with 40 and 50% salt concentrations were the best products, but had strong, salty taste. The product prepared with 5% salt concentration became rancid and spoiled after two weeks. Those prepared with 10, 20, and 30% salt concentrations were acceptable products from the standpoint of saltiness, rancidity, and overall odor scores.
All the products except those prepared with the lowest (5%) salt concentration, were not spoiled and still retained the original boiled fish characteristics for four weeks of storage at temperatures and humidities resembling tropical conditions. After four weeks of storage, the products became progressively drier and toughened as they became more dehydrated.

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The Dugong, Halicore dugong, inhabits around the shallow sea of the Indian and the Pacific ocean, and lives mainly on marine algae.
The purpose of the present study is to examine the component fatty acid of the Dugong oil by gas-liquid chromatography using hydrogen flame ionization detector.
The sample oil (Table 1) was converted to fatty acid methyl ester by alkali-catalyzed methanolysis followed by silicic acid column treatment.
As shown in the Tables 2, 3 and 4, the presence of eighteen kinds of fatty acids ranging from 8 to 20 carbon atoms were detected, i.e.: Normal saturated acids (8, 10, 12, 14, 15, 16, 16, 17, 18 and 20 C-atoms), monoenoic acids (12, 14, 16 and 18 C-atoms), dienoic acids (14, 16 and 18 C-atoms), trienoic acid (18 C-atom), and tetraenoic acid (20 C-atoms).
According to the results, the most prominent is monoenoic C₁₈ acid (41.3%), followed by saturated C_l6 acid (23.0%), and the amount of these acids was more than 64% of the total fatty acids. The total saturated and unsaturated fatty acids contents are 38.7 and 61.3%, respectiveiy.

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The difference in the quality of Kombu from part to part was previously reported^{l, 2)} i.e., the central part (including the base) of the blade is thicker and more palatable than the marginal part (including the apex). The present study was carried out to investigate the difference in more detail. Two specimens Makombu were collected from the Omori and Kakkumi districts near Hakodate City, in the southern part of Hokkaido. They are rather higher in quality than the average; the quality of the former products is not so bad, and that of the latter is evaluated the best of all the kinds of Kombu in the market.
The blade was cut into small pieces to determine the quality according to the width and length of the plant as shown in Figs. 1 and 2. Amino acid pools of the 70% ethanol extracts from these pieces were determined by amino acid analyzer. The results are shown in Tables 1 and 2. Total extractive nitrogen, and extractive amino nitrogen determined with ninhydrin and calculated as leucine, were also shown. In addition, the thickness of the pieces was measured with a micrometer.
From Tables 1 and 2, the following results were drawn: The less amount of amino nitrogen was found in the stipe part which is called Nekombu, but there was a lot of protein nitrogen. Alanine was relatively rich in this part, too. The amounts of glutamic and aspartic acids were highest in the central part, especially in the base part. These parts prevalent to be the most palatable. The palatability is supposed to be due to the amount of these amino acids. Generally, the amounts of amino acids and amino nitrogen were low in the marginal part, especially low in the marginal part where the color changes into reddish-brown. No clear difference in the amount of amino acid was found between the two Kombu specimens.
The amounts of tryptophan, histidine, and arginine were very low or almost negligible. U-compound²⁾ was present only in the central part. An unknown substance like levulinic acid was found in every sample pieces.

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The presence of a new biologically active peptide which has been named callopeptide by the authors was presumed in the digested muscle of fur seal as follows: Skeletal muscle brei including a small portion of bone or internal organs was digested by protease after eliminated fats and oils. Ethanol was added to the digested muscle, the soluble portion obtained at alcohol concentration of 60 to 80 percent passed through a column of Sephadex G-25 after concentrated under reduced pressure to remove the alcohol, and the effluents were divided into four fractions as in Figs. 1 and 2. It was observed that the second fraction develops an intense color by biuret reaction and shows the presence of 12 unknown peptides and small amounts of free amino acids on the chromatogram of amino acid analysis using an analyzer (Table 4).
When the test animal (rabbit, cat, etc.) was affected with an aliquot of the second fraction, a strong capillary vasodilatory effect was observed which was disappeared by the complete hydrolysis of this fraction. The biological actions of the fraction are, however, differed from those of vasoactive peptide for instance, bradykinin as shown in Tables 1 and 2, and it was presumed that the digested fur seal muscle contains a new type of biologically active peptide.

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In a previous paper¹⁾, one of the authors reported that the dried purple laver, porphyratenera, markedly reduced plasma cholesterol in rats. In order to investigate the mechanism of lowering effect of this algae, cholesterol contents in feces of rats fed with or without purple laver were determined. Much more cholesterol was found in feces of rats fed with purple laver than that of control. The increment of excretion of cholesterol must be one of the reasons for reducing plasma cholesterol.

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Two feeding trials with rats were carried out to determine the possible presence of unidentified growth factor in fish solubles or whole meal.
In the first test four groups of weanling rats, 3 males and 4 females each, were pair-fed for 6 weeks. To the control group was administered a basal diet containing casein at 15% level and to the comparable groups, test diets in which 15 percent of the amount of casein was replaced isonitrogenously by jack mackerel meat meal, liver solubles and liver meal from bluefin tuna respectively.
The results showed that supplement with the two fish materials improved protein efficiency ratio (PER) of females in the latter half period though not in the former half period of feeding. The effect of fish materials was not observed in males during the entire feeding period.
The second test was carried out similarly, but two levels of dietary protein, 15 and 8%, were provided and saury fish solubles was used as the sole substitute. At 15% level of protein, supplementing basal diet with the fish solubles had no effect on the growth of rats of both sexes, and this trend was uninfluenced by preventing coprophagy in rat.
However, at 8% protein level, the fish solubles improved PER in females by 12 percent as the test period progressed.

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To ascertain the benefical effect of fish solubles as supplement to a casein-containing basal diet on the growth of female rats, as previously reported, two feeding experiments were also run with other experimental materials.
It was indicated that all fish solubles examined tended to give good influence on the growth and to improve the protein efficiency ratio (PER) for females in the latter feeding period. Thus it was found that the previous results are reproducible.
The effect was particularly evident with the fish solubles of Alaska pollack, the relative PER with it exhibiting 123 to that of basal ration, 100.

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1. The requirement of young carp for folic acid have been studied, using the basal diet divised by HALVER et al.
2. In feeding trials for 16 weeks, no deficiency symptoms was observed in gross observation. Moreover, addition of sulfanilamide to the diet or omission of both folic and p-aminobenzoic acids from the diet revealed no effect on growth and mortality.
3. Under the experimental conditions adopted, inconclusive result was obtained on the requirement for folic acid.

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