. vision should also be made for ventilation without admitting light or drafts. The barrel den shown in figures 3 to G is merely a clean barrel, having a smooth interior, surrounded by dry sawdust, within a wooden box. In one head of the barrel is an entrance hole 8 inches wide and 10 inches high. A similar 74743°—Bull. 795—17 2 Fig. 4.—Horizontal longitudinal section of barrel den.

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Keywords: ., bookauthordearbornned1865, bookcentury1900, bookdecade1910, books