土壌中に於ける鉤仔虫の垂直分布に関する研究 第1報 夏季土壌中に於ける鉤仔虫の垂直分布に関する実験的研究

In the experiments carried out for the purpose of finding out the manner of hatching of hookworm eggs embedded in various layers of the soil in farm fields throughout the Okayama Prefecture during summer months and to see in what different depths these larvae are found under various conditions, the author obtained the following results. 1) Hookworm larvae hatch readily and their longevity of life seems to be well over eight weeks. 2) In fair weather these larvae generally avoid the layer close to the surface of ground between the hours, noon to 2 o'clock in the afternoon and seeking refuge in a cooler layer of the soil, more larvae are found in the deeper layers. However, on rainy days these larvae migrate to the layer close to the surface in large numbers.