Report of the Secretary, 第 51 卷 |
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00 Instructor abe Sept acid American foul brood ammonia amount annual Autopsy of virus beetles Black Locust Bldg body wt Bordeaux mixture Bulletin carbon dioxide Cholera lesions Claimed Clear clover College Hall course crops disease ditch drain East Lansing Engineering erect Experiment Station farm farmers feet Fertilizer flowers Found Freshmen gallons grass grms Grower hyperimmunized Immune pig inches insecticide insects Introduced from Europe June 30 kerosene killed laboratory leaves lime-sulphur Lymph glands Manufacturer's sample Material injected Math Michigan NaCl from virus nitrogen Norway Spruce Nursery oxygen Partly cloudy Passalus cornutus perennial petechiae on kidneys Phosphoric Acid Pig Weight placed plant Potash Prof Professor respiration respiratory quotient scale insects seeds Seniors soil solution Sophomores species spraying stake Sub-fresh subcutaneously tested as follows tile tion Total tracheae trees vapor virus NaCl virus pig weed winter yellow
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第 519 頁 - Some limes are so sluggish in slaking that it is difficult to obtain enough heat from them to cook the mixture at all, while other limes become intensely hot on slaking and care must be taken not to allow the boiling to proceed too far. If the mixture is allowed to remain hot...
第 519 頁 - As soon as it is well slaked water should be added to cool the mixture and prevent further cooking. It is then ready to be strained into the spray tank, diluted, and applied.
第 526 頁 - There are two recognized infectious diseases of the brood of bees, now known as American foul brood and European foul brood. Both diseases weaken colonies by reducing the number of emerging bees needed to replace the old adult bees which die from natural or other causes. In neither case are adult bees affected, so far as known. The means used by the beekeeper in deciding which disease is present is the difference in the appearance of the larvae dead of the two diseases. That the diseases are entirely...
第 528 頁 - ... which sometimes extends for several inches before breaking. This ropiness is the chief characteristic used by the beekeeper in diagnosing this disease. The larva continues to dry down and gradually loses its ropiness until it finally becomes merely a scale on the lower side wall and base of the cell.
第 529 頁 - The earliest indication of the disease is a slight yellow or gray discoloration and uneasy movement of the larva in the cell. The larva loses its well.rounded, opaque appearance and becomes slightly translucent, so that the tracheae may become prominent, giving the larvae a clearly segmented appearance.
第 529 頁 - As the healthy brood emerges the comb shows the scattered sunken cappings covering dead larvae, giving it a characteristic appearance. Pupae also may die of this disease, in which case they too, dry down, become ropy, and have the characteristic odor and color. The tongue frequently adheres to the upper side wall and often remains there even after the pupa has dried down to a scale.
第 594 頁 - The evidence gathered seems to indicate that the vapors of gasoline, kerosene, carbon disulphide and the like, after absorption into the insect-body, become mainly effective through some tendency their presence exerts to prevent oxygen absorption by the tissues. Lime-sulphur is a special rather than a general contact insecticide. Its strong, persistent reducing power, and its ability to soften the wax about the margin of a scale insect like the San Jose scale are the important properties that make...
第 529 頁 - Agriculture.) after the pupa has dried down to a scale. Younger unsealed larvae are sometimes affected. Usually the disease attacks only worker brood, but occasional cases are found in which queen and drone brood are diseased. It is not certain that race of bees, season, or climate have any...
第 528 頁 - The larva gradually sinks down in the cell and becomei darker in color and the posterior end lies against the bottom of the cell. Frequently the segmentation of the larva is clearly marked. By the time it has partially dried down and has become quite dark brown (coffee colored) the most typical characteristic of this disease manifests itself. If a match stick or toothpick is inserted into the decaying mass and withdrawn the larval remains adhere to it and are drawn out in a thread which sometimes...
第 529 頁 - The majority of the larvae which die of this disease are attacked after being sealed in the cells. The cappings are often entirely removed by the bees, but when they are left they usually become sunken (fig.