| 释义 |
▪ I. ‖ hemera1 Obs.
Pl. -æ; in 6 erron. hæmerae, 7 hæmere.
= ephemera 1 (q.v.).
c1590Greene Fr. Bacon x. 124 The flies haemerae..take life with the sun and die with the dew. 1614Scou. Venus (1876) 21 As the flies Hæmere we do see To leaue their breath their life being scarce begunne.
▪ II. hemera2 Palæont. and Geol.|ˈhɛmərə|
Pl. -æ.
[mod.L., f. Gr. ἡµέρα day.]
A period of geological time in which any particular species was most abundant as represented in strata; an interval between times when two successive species were dominant. Hence ˈhemeral a.
1893S. S. Buckman in Q. Jrnl. Geol. Soc. XLIX. 481 For a palaeontological purpose... I propose the term ‘hemera’... I wish to use it as the chronological indicator of the faunal sequence. 1898― Ibid. LIV. 443 The hemeral names are taken from the names of ammonites. Ibid., The shortest geological time-division is a hemera: that is, the time during which a particular species..had dominant existence. Ibid. 448 The genera Dactylioceras and its allies..almost disappear with the close of the hemera bifrontis. 1902― in Geol. Mag. Dec. 555 A ‘hemera’ was designed to mark the time from..when one species or set of species becomes dominant to the time when another..does so. 1920Q. Jrnl. Geol. Soc. LXXVI. 63 The range of strata which Mr. Richardson has divided into seven or at the most eight hemeræ cover, according to my more detailed subdivisions, thirty-two hemeræ, and should afford a good test as to whether this more detailed method of dating makes for greater precision. 1933W. J. Arkell Jurassic Syst. Gt. Brit. i. 20 Nine years later, finding that there were still some who considered that a hemera was simply a subdivision of a zone, Buckman published a fresh explanation. Ibid. 27 In the course of an argument with Buckman over his insertion of an excessive number of hemeræ into the time-table of the Corallian rocks, I attempted to justify my view..that many of his hemeral indices lived side by side on the same sea-bed. 1966D. T. Donovan Stratigr. vii. 160 Several other time terms have been proposed but have never achieved general recognition. Perhaps the most notorious is the hemera. Ibid. 161 Hemerae were much used by English Jurassic workers for about forty years, but hardly at all by anyone else. |