Page:EB1911 - Volume 07.djvu/731

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CYSTOLITH
709

corresponding to the longitudinal, the large flagellum to the transverse flagellum of that group.

After E. Ray Lankester, Ency. Brit., 9th ed.
Cystoflagellate Protozoa.
1 and 2, Young stages of Noctiluca miliaris.
 a, the big flagellum; the unlettered filament becomes the oral flagellum of the adult.
n, nucleus.
s, the so-called spine (superficial ridge of the adult).

3 and 4, Two stages in the fission of Noctiluca miliaris, Suriray.
n, nucleus.
N, food-particles.
t, muscular flagellum.

5. Noctiluca miliaris, viewed from the aboral side (after Allman, Quart. Jour. Mic. Sci., 1872).

a, entrance to atrium or flagellar fossa (= longitudinal groove of Dinoflagellata).
c, superficial ridge.
d, big flagellum (= flagellum of transverse groove of Dinoflagellata).
h, nucleus.
6. Noctiluca miliaris, acted upon by iodine solution, showing the protoplasm shrunk away from the structureless pellicle.

a = entrance to atrium.

7. Lateral view of Noctiluca miliaris.
a, entrance to atrium.
b, atrium.
c, superficial ridge.
d, big flagellum.

e = mouth and gullet, in which is seen Krohn’s oral flagellum (= the chief flagellum, or flagellum of the longitudinal groove of Dinoflagellata).
f, broad process of protoplasm extending from the superficial ridge c to the central protoplasm.
g, duplicature of pellicle in connexion with superficial ridge.

h, nucleus.

The reproduction of Noctiluca has been fairly made out; in the adult state it divides by fission down the oral groove; as a preliminary the external differentiations disappear, and the nucleus divides by modified mitosis; then the external organs are regenerated. Under circumstances not well made out, conjugation between two adults takes place by their fusion commencing at the oral region; flagella and pharynx disappear and the nuclei fuse, while the cytoplasts condense into a sphere. The nucleus undergoes broad division, the young nuclei pass to the surface, which becomes imperfectly divided by grooves into as many rounded prominences as there are nuclei (up to 128 or 256); and these become constricted off from the residual useless cytoplasm as zoospores with two unequal flagella, which were at first regarded as Dinoflagellates, of which they have the form (figs. 5, 6). The metamorphosis of these has not yet been observed.

Literature.—E. Suriray, Magazin de zoologie, 1836; G. J. Allman, Quarterly Journal of Microscopic Science, n.s. xii., 1872; L. Cienkowsky, “Zoospore formation in Noctiluca,” Archiv f. mikroskopische Anatomie, vii., 1871; R. Hertwig, “Leptodiscus,” Jenaische Zeitschrift, xi., 1877; C. Ischikawa, Journal of the College of Science (Tokyo, 1894), xii., 1899; F. Doflein, “Conjugation of Noctiluca,” Zoologische Jahrbücher, Anatomie, xiv., 1900; C. A. Kofoid, “Craspedotella,” in Bull. Mus. Comp. Zool. Harvard, xlvi., 1905; O. Bütschli, “Mastigophora,” in Protozoa (Braun’s Thierreich, vol. i., Protozoa) (1883–1887). (M. Ha.) 


CYSTOLITH (Gr. κύστις, cavity, and λίθος, stone), a botanical term for the inorganic concretions, usually of calcium carbonate, formed in a cellulose matrix in special cells, generally in the leaf of plants of certain families, e.g. Ficus elastica, the india-rubber plant.


CYTHERA (mod. Cerigo, but still officially known as Cythera), one of the Ionian islands, situated not less than 150 m. from Zante, but only about 8 m. from Cape Malea on the southern coast of Greece. Its length from N. to S. is nearly 20 m., and its greatest breadth about 12; its area is 114 sq. m. The surface is rocky and broken, but streams abound, and there are various parts of considerable fertility. Two caves, of imposing dimensions, and adorned with stalactites of great beauty, are the most notable among its natural peculiarities; one is situated at the seaward end of the glen of the Mylopotamus, and the other, named Santa Sophia, about two hours’ ride from Capsali (Kapsali). Less of the ground is cultivated and more of it is in pasture land than in any other of the seven islands. Some wine and corn are produced, and the quality of the olive oil is good. The honey is still highly prized, as it was in remote antiquity; and a considerable quantity of cheese is manufactured from the milk of the goat. Salt, flax, cotton and currants are also mentioned among the produce. The people are industrious, and many of them seek employment as labourers in the Morea and Asia Minor. Owing to emigration, the population appears to be steadily diminishing, and is now only about 6000, or less than half what it was in 1857. Unfortunately the island has hardly a regular harbour on any part of the coast; from its situation at the meeting, as it were, of seas, the currents in the neighbourhood are strong, and storms are very frequent. The best anchorage is at San Nicolo, at the middle of the eastern side of the island. The principal village is Capsali, a place of about 1500 inhabitants, at the southern extremity, with a bishop, and several convents and churches; the lesser hamlets are Modari, Potamo and San Nicolo.

There are comparatively few traces of antiquity, and the identification of the ancient cities has been disputed. The capital, which bore the same name as the island, was at Paleo-Kastro, about 3 m. from the present port of Avlemona. In the church of St Kosmas are preserved some of the archaic Doric columns of the famous temple of Aphrodite of Cythera, whose worship had been introduced from Syria, and ultimately spread over Greece. According to the accepted story, it was here that the goddess first landed when she emerged from the sea. At a very early date Cythera was the seat of a Phoenician settlement, established in connexion with the purple fishery of the neighbouring coast; it is said that it was therefore called Porphyris (cf. Pliny iv. 18, 19). For a time dependent on Argos, it became afterwards an important possession of the Spartans, who annually despatched a governor named the Cytherodices. In the Peloponnesian war, Nicias occupied the island, but in 421 it was recovered by Sparta. Its modern history has been very much the same as that of the other Ionian islands; but it was subject to Venice for a much shorter period—from 1717 to 1797.

See the works referred to under Cephalonia, and also Weil, in Mittheil. d. deutsch. Inst. zu Athen (1880), pp. 224–243.


CYTISINE (Ulexin, Sophorin), C11H14N2O, an alkaloid discovered in 1818 by J. B. Chevreul in the seeds of laburnum (Cytisus Laburnum) and isolated by A. Husemann and W. Marmé in 1865 (Zeit. f. Chemie, 1865, i.p. 161). It is also found in the seeds of furze (Ulex europaeus), Sophora tormentosa, and Euchresta horsfieldii. It is extracted from the seeds by an