| 释义 |
isepiptesis, isopiptesis rare.|aɪˌsɛpɪˈ(p)tiːsɪs, aɪsəʊpɪˈ(p)tiːsɪs|
[a. G. isepiptese (A. T. von Middendorff 1855, in Mém. Acad. Imp. Sci. St. Pétersbourg, 6e série, Sci. nat. VIII. 8), f. Gr. ἐπίπτησις flying down upon.]
A line (either imaginary or on a map) connecting points which migrating birds reach at the same time. Hence isepiˈptesial a.
1875A. Newton in Encycl. Brit. III. 768/1 His [sc. Middendorff's] chief object has been to trace what he has termed the isepipteses... Assuming that the advance is directly across the isepiptesial lines..the whole course of the migration is thus most accurately made known. 1926A. L. Thomson Probl. Bird-Migration viii. 132 His [sc. Middendorff's] method was to plot out ‘isepipteses’, or isochronal lines, joining up all localities corresponding with each other as to their average dates for the arrival of particular summer visitors. [1962C. D. Sherman tr. Dorst's Migrations of Birds viii. 233 He [sc. Middendorff] plotted these data on a map, linked the localities which migrants reach on the same date and thus obtained a line he called the isopiptes..(this line was later named the isochronal line). ] |