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SOAKED BREAST MUSCLE OF CHICKEN IN COLD STORAGE 2 YEARS. [Zeiss: 16mm. objective, apochromatic; No. 12 ocular, compensating.]

[graphic]

FIG. 1.-LONGITUDINAL SECTION SHOWING VACUOLATED DEGENERATION. [Zeiss: 4mm. objective, apochromatic; No. 8 ocular, compensating.]

[graphic]

FIG. 2.-LONGITUDINAL SECTION SHOWING VARIED AND EXTENSIVE DEGENERATION.
BREAST MUSCLE OF CHICKEN IN COLD STORAGE 4 YEARS.

[Zeiss: 16mm. objective, apochromatic; No. 12 ocular, compensating.]

Uor M

ical appearance is more than explained by the structure of the tissue as revealed under the microscope.

Plates XII and XIII show the character of the intestine of a fresh chicken and also of a chicken in cold storage for six months It will be observed that the muscular coats of the cold-stored chickens have quite lost their characteristic structure. Apparently they consist almost exclusively of the sheath of the fibers which, if they contain muscle substance in any quantity, have it so altered chemically that standard muscle-staining dyes do not affect it. What remains of the individual fibers is a mass, loosely put together, which would offer but little resistance to the,migration of bacteria.

So far as the cellular portions of the intestine are concerned they are reduced to a minimum. Either the intestines are obliterated or the cells are so dried and disintegrated that they are mere fragments. Though the cell, as a whole, is in bad condition, the nucleus has apparently offered greater resistance to the corroding action than has the cytoplasm of the cell.

GENERAL DISCUSSION.

Bacteria and enzymes are most directly concerned in the question of flesh decomposition, the effect of air, light, temperature, humidity, and such conditions as are ordinarily considered responsible for alterations in organized tissues being in reality factors influencing the growth or activity of one or the other, or both, of the agencies stated. The investigations of flesh decomposition which have been reported have been conducted usually at room temperatures or at body heat. Such studies at temperatures near 0° C. are almost entirely wanting, probably because of the general idea that enzymic and bacterial activities cease at or about zero.

a

RESISTANCE OF BACTERIA TO LOW TEMPERATURES.

The resistance of bacteria to low temperatures is well known, and a number of investigators have subjected various species of organisms to almost the lowest limit of modern cold. In 1884 Pictet and Young exposed B. anthracis, B. subtilis, Micrococcus leuteus, the bacillus of symptomatic anthrax, beer yeasts, and smallpox vaccine to temperatures varying from -70° C. to -130° C. and for periods of from 20 to 108 hours. The bacteria proper were not destroyed; the yeasts were intact microscopically but their functions were lost, as was also the activity of the smallpox vaccine. Macfayden exposed a number of bacteria, both benign and pathogenic, to the temperature of liquid air (-190° C.), first for a period of 24 hours and

a Compt. rend., Jan. to June, 1884, p. 747,

b Lancet, 1900, 1 [849]: 1130.

b

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