| 释义 |
spicule|ˈspɪkjuːl|
[a. F. spicule, or anglicizing of spicula, spiculum.]
1. Bot.
a. A floral spikelet (cf. spicula 3).
b. (See quot. 1855.)
1785Martyn Lett. Bot. xiii. (1794) 136 Spicules triangular. [Note] These are the little assemblages of flowers, or ultimate subdivisions of the panicle or whole. Ibid. 137 The spicules are ovate, and on short foot-stalks. 1855Miss Pratt Flower. Pl. I. 5 Spicules, two little wing-like pieces often seen at the base of the leafstalk, as in the Rose.
2. One or other of the points of the basidia or sporophores in fungals.
1843Penny Cycl. XXV. 183/1 The hymenium [of Exidia glandulosa] is covered with spicules. 1866Treas. Bot. 1088/2 In such Fungi as agarics the sporophores..bear generally four little points called spicules,..on which the spores are seated. In Tremella the sporophores are globular or quadripartite, the spicules being drawn out into long threads. 1875Cooke Fungi 22 With which also their structure agrees, excepting in the development of spicules.
3. In sponges: = spiculum 3.
1846Dana Zooph. (1848) 645 The cortex..shows numerous minute granules or spicules of lime, disseminated through it. 1860Maury Phys. Geog. xiv. 616 note, A considerable number of silicious spicules of sponges. 1885J. E. Taylor Brit. Fossils i. 9 When alive the outer layer of ‘sponge-flesh’ is usually permeated with myriads of exceedingly small solid bodies, called fibres and spicules.
attrib.1887Sollas in Encycl. Brit. XXII. 416/1 A thin layer of organic matter, known as the spicule sheath, forms an outer investment to the spicule.
4. Zool. A needle-like or sharp-pointed process or part.
1861J. R. Greene Anim. Kingd., Cœlent. 160 In some species of Alcyonidæ proper, the spicules attain a comparatively large size. 1872H. A. Nicholson Palæont. 66 All the Radiolaria possess hard structures in the form of siliceous spicules or a siliceous test. 1890Science-Gossip XXVI. 198 The ovate individuals..showed the mouth or osculum fringed with spicules standing erect.
5. A fine-pointed piece, splinter, or fragment of some hard substance; a spicula or spiculum.
1835J. Paget Let. 16 Apr. in S. Paget Mem. & Lett. Sir J. Paget (1901) 57 The same appearances have been noticed in our dissecting-rooms, where they have been attributed to the deposition of small spicules of bone (which, indeed, they somewhat resemble). 1865Milton & Cheadle N.-W. Passage by Land xv. 301 The fallen timber lay as thickly and entangled as the spiculæ in the children's game of spelicans. 1878Huxley Physiogr. 62 A nucleus from which six little spicules or rods of ice are shot forth. 1879Khory Digest Med. 37 Under the microscope granular matter, and spheres with spicules sticking on them, are seen. 1895Hoffman Beginnings of Writing 37 A small bundle of needles, spicules of bone, or fish spines.
6. Astr. Any of numerous short-lived, relatively small radial jets of gas observed to occur in the sun's atmosphere in the chromosphere and lower corona.
1945W. O. Roberts in Astrophysical Jrnl. CI. 136 Small spikes of chromospheric material, observed in Hα with the coronagraph and quartz-polaroid monochromator are described. These spicules, seen in polar regions of the sun, have very brief lifetimes, amounting on the average to 4 or 5 minutes. 1948, etc. [see jet n.3 4 c (ii)]. 1974Bray & Loughhead Solar Chromosphere ii. 60 Spicules in the polar regions of the sun tend to follow the direction of the overlying coronal rays. 1978Pasachoff & Kutner University Astron. viii. 191 Spicules are best seen when we are looking off the edge of the sun, beyond the limb. |
