It is customary that the naked-eye examinations of lustre and colour (fresh, blue, or blackened) and the examinations of flavour and taste decide whether or not the canned crabmeat is exportable. An expert who is experienced in carrying these examinations is responsible for the decision.
Two ranges of the content of SH₂ which were determined by me with Almy's method in the juice from the canned crabs (Table 1) correspond to the expert's two classifications, exportable and non-exportable. A range of 2-8mg. of SH₂ was found in 100 liter of the juice of the exportable class, 95% of which contains 2-7mg. On the other hand, the same substance amounts to 12-500mg. in the same volume of the juice of the non-exportable, 11-20mg. being found in 36.6% and 20-40mg. in 40% of the material examined.

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With the object of applying the van Slyke method to the study of the nutritive value of the protein in feeding-stuffs, we investigated first the extent of the error arising from the presence of interfering substances, and then searched for the simplest method to enable us to obviate, or at least to reduce, the chief source of error.
Casein was hydrolyzed with or without the addition of the following substances: starch, sucrose, filter paper, olive oil, and agar-agar. The addition of fat influences the analytical results slightly, while the addition of carbohydrate interferes to a much greater extent with the determination of amino acids, by the method under consideration. These results coincide with those of Y_ANAGAWA and N_ISHIMURA.
Hence, before subjecting the sample to the van Slyke method, it is quite necessary to treat feeding-stuffs so that all the proteins separated from the interfering substances. By treating the sample in such a manner as to boil with water and precipitate with acetic acid, it was easily possible to free the proteins from most of non-protein nitrogenous substances and hotwater-soluble carbohydrates, of which the main parts of the carbohydrates in feeding-stuffs consist. Our experiment showed that the recovery of nitrogen in the form of coagulable nitrogen amounted in the cases of sardine muscle and soy-bean to 94-95% of the protein nitrogen after the Stutzer method, and to 91% of the protein nitrogen in the case of silk-worm pupa.
Even following the above method, the fibre, which is contained only in the feeding-stuffs of plant origin, will remain in the coagulable protein part. Thereafter, we made further experiment, in which casein mixed with equal amount of fibre was analyzed on one hand by the original van Slyke method, and on the other hand by the Hamilton method, and by the another modified method in which analysis was made in the filtrate obtained after removal of the residue insoluble in 20% HCl. From the results obtained by these three methods, it was evident that there is no choice, on the whole, between them. Hence, we conclude that it is not necessary to treat the sample of feeding-stuffs with such a complex manner as H_AMILTON recommends, if we analyze the isolated coagulable protein above-mentioned, which is free from most of the interfering substances.

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In the previous paper, I have reported on the bactericidal activity of mineral acids, saturated and unsatura'ed monobasic acids and saturated dibasic acids on some putrefactive and pathogenic bacteria. The present paper deals with the bactericidal activity of the juices of various fruits on Bacillus typhosus and Vibrio cholerae using the method described in the previous paper.
The results obtained are summarized in the table 2. Juices of bitter orange, lemon, Chinese citron, grape, mandarin orange, strawberry, peach, apple, cherry, pear, Japan-medlar stand in descending order of bactericidal activity. The juice of bitter orange (Citrus aurantium var. Jonas) has pH values from 3.6 to 4.2 and is by far the strongest of all the fruit-juices and amineral acid examined when compared at the same pH values. Some substance or substances other than acid contained in bitter orange appear to account for such strong bactericidal action.

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The change in length and diameter of cotton cords stretched in water was studied in the present experiment by just the same method as that in the previous one with unloaded cords.⁽¹⁾ The temperature of water ranged 25_??_31°C. From the results we know that: (1) the ratio l-l₀/l₀, where l and l₀ are the lengths of the cord at the commencement and after t hours' immersion in water respectively, varies with t in a similar way irrespective of the tension of yarns (Fig. 1); (2) the relation between (l-l₀/l₀)₂₄ at t=24 and the mean tension of a yarn, w/3vgr., is as shown in Fig. 2; (3) the final (t=24) change in length, Δl, and that in diameter, Δr, whether positive or negative, are related with each other in accordance with the formula Δl=-BΔr, where B is a constant depending only on the initial length, l₀, and the initial diameter, r₀, as well as on the number of twists per length of the cord, N, and that of the thread, n. The same formula is valid for the changes which take place, when the cord is loaded in air, or when it is put in water without load. Under the supposition that the length of each yarn which constructs a cord remains unchanged, we have, denoting the ratio of the mean radius of a yarn to the radius of the cord by a,
l²+4π²(N-n)²(ar)²=const. Thence 2l₀Δl+4π²(N-n)²a²2r₀•Δr=0, and B=4π²(N-n)²a²r₀/l₀.
The values of B calculated by this formula coincide well with those values obtained from the slope of straight lines in Fig. 3 (Tab. 1). (4) The relation between (l-l₀/l₀)₂₄ and (r-r₀/r₀)₂₄ is given as (l-l₀/l₀)₂₄=-.27(r-r₀/r₀)₂₄ (Fig. 4).

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The material on which the present paper is based was obtained from summer to winter of 1931 from various parts of the city of Tokyo and consists of 420 items. Of these 205 (48.8%) were found contaminated with Bacillus coli. In these, 50 (16%) were by E. coli. The other colon bacteria found in the material at our disposal are referable to other 7 species of Escherichia, 2 species of Alcaligenes, and Aerobacter. Not a single case of Bacillus typhosus was met with. Table 1 tabulates our results.

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The Japanese food matter called “Kamaboko” is prepared by steaming fish paste which is seasoned with salt, sugar and “mirin.”⁽¹⁾ It produces some mucous matter on its surface when left in a non-antiseptic condition. Our study on the bacteria in this mucous matter resulted to obtain 14 species from 45 cultures.
Of these, 15 cultures were found referable to Micrococcus, 2 to Rhodococcus, 9 to Leuconostoc, 11 to Bacillus, 4 to Achromobacter, 4 to Flavobacterium. Among them those of Bacillaceae group were found to be motile, but Bacteriaceae group to be non-motile, and the following 6 species appear to us to be new to science.
1. Micrococcus gilvus n. sp.
It resembles Micrococcus ochraceus. However, it differs in the following characters.
Nitrates: reduced to nitrites; Broth: slight turbid with sediment (viscid), no pellicle; In a broth medium containing sugar, growth was abundant.
2. Micrococcus solidus n. sp.
It possesses all the characteristics of the genus Micrococcus as given by BERGEY (1930). But it is quite different from any species of this genus which does not undergo chromogenesis but liquefies gelatin.
Characterisation runs as follows: -
Morphology: -Spheres (1.0 ?? 1.3μ dia.), occurring in irregular masses. Gram-positive. Nonmotile.
Cultural features: -Agar colonies: irregular, dull, flat, opaque, white, lobate or auriculate, granular; Gelatin colonies: concave, cloudy, white, lobate, crateriform liquefaction; Gelatin stab: stratiform liquefaction; Potato: graysh-white, dull, dry; Broth: turbid with pellicle and scanty sediment (viscid).
Physiological characters: -Litmus milk: acid, coagulation, peptonization, litmus reduced; Indol: not formed; Nitrates: reduced to nitrites; Fermentations: acid was produced from dextrose, sucrose, lactose, mannit, glycerine, salicin, raffinose; Starch not hydrolyzed. Opt. temp. 27°C.
3. Bacillus canus n. sp.
It resembles Bacillus clostroides, differs in the following particulars.
Potato: graysh-white, rugose; Broth: slight turbid with slight pellicle; In a broth medium with sugar growth was abundant.
4. Bacillus catenatus n. sp.
It possesses all the characteristics of the genus Bacillus as given by BERGEY (1930), but not referable to any species of it.
Characterisation is as follows: -
Morphology: -Rods (0.8 ?? 1.0×3.5 ?? 7.0μ), occurring in long chains, peritrichous flagella; Gram-positive; Spores (0.8×1.8μ), central.
Cultural features: -Agar colonies: curled or irregular, rough, flat or raised, gray, auriculate, curled or granular (internal structure); Agar stroke: echinulate or spreading, dull, rugose, flat or raised, opaque, gray to brown; Gelatin stab: liquefaction was slowly (napiform ?); Potato: dark-orange-white to brown, dull, dry, medium darkened; Broth: slight turbid with slight pellicle.
Physiological characters: -Litmus milk: alkaline, peptonized; Indol: not formed ; Nitrates: reduced to nitrites; Fermentation: acid was produced from dextrose and sucrose: Starch not hydrolyzed. Opt. temp. 35°C.
5. Achromobacter immotum n. sp.
It possesses all the characteristics of the genus Achromobacter as given by BERGEY (1930), but differing from any one of those species genus Achromobacter which do not liquefy gelatin and are non-motile. Characterisation is as follows: -
Morphology: -Rods (0.8 ?? 0.9×1.8 ?? 4.0μ), with rounded ends occurring singly, in pairs and in short chains. Non-motile.

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It is well known that fishes while jostling in the fishing net vomit their taken food during the manipulation of the fishing. Whether this vomiting is simply a mechanical disgorging due to the violent jostle of the fish in the net, or a real vomiting produced by the excitement of the nervous vomiting center as is observable in the case of higher vertebrates, is still unknown. Indeed, it has not yet been proved, whether the low class vertebrate, such as the fish, has the vomiting center, or not.
The writer used apomorphine hydrochloride to test if fishes react to the emetic. 0.2-1.0 c.c. of its 0.5% solution was injected into the body cavity of various sea fishes, to which sufficient food had previously been given. The reaction was extremely remarkable; almost all the fishes thus treated vomited entirely their stomach contents soon after the injection of the emetic. The control experiment was also done by the injection of the distilled water. Negative reaction was, however, obtained.
Since, thus, apomorphine hydrochloride is equally applicable as an emetic to the fish and it is the stimulant of the vomiting center in the higher vertebrates, the writer makes suggestion on the existence of the vomiting center in the fish.

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