which the oral arms become fused together to form a proboscis. Nine families, three of Semaeostomeae, six of Rhizostomeae:—
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Modified from a coloured plate in Prince of Monaco's series. |
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Fig. 14.—Atolla bairdi. After O. Maas. |
1. Pelagiidae.—Semaeostomeae with wide gastric pouches not united by a ring-canal. Pelagia, an oceanic genus with direct development. Chrysaora (fig. 3b), a common British medusa, with a scyphistoma stage and alternation of generations. Dactylometra, a common American medusa of the Atlantic shores, differs from Chrysaora in small points.
2. Cyaneidae.—Semaeostomeae with sixteen gastric pouches sending off canals to the margin not united by a ring-canal; tentacles in bunches on the margin. Cyanea (fig. 15), represented in the British fauna by two species.
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After E. Haeckel, from System der Medusen, by permission of Gustav Fischer. |
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Fig. 15.—Cyanea (Desmonema) anasethe, about two-thirds life-size. |
3. Ulmaridae.—Semaeostomeae with gastric pouches relatively small, sending off branching canals to the margin, where they are united by a ring-canal. Ulmaris, from the South Atlantic, has only eight adradial tentacles. Aurelia (fig. 2), with numerous marginal tentacles, is one of the commonest and most familiar of jellyfishes.
4. Cassiopeidae.—Rhizostomeae with subumbral musculature arranged in feather-like arcades (Arcadomyaria, Maas); oral arms pinnate. Cassiopeia.
5. Cepheidae.—Rhizostomeae with subumbral musculature in radial tracts (Radiomyaria, Maas); oral arms bifid. Cephea, Cotylorhiza.
6. Rhizostomatidae (Pilemidae).—Rhizostomeae with subumbral musculature in circular bands (Cyclomyaria); oral arms bifid or very complicated; sixteen radial canals. Rhizostoma (Pilema) is a very common genus (fig. 3a).
7, 8, 9. The families Lychnorhizidae, Leptobrachidae and Catostylidae resemble the preceding in the arrangement of the musculature. In Lychnorhizidae only eight of the sixteen radial canals reach the ring-canal; the genus Crambessa is the best-known representative of the family. In the other two families there are eight radial canals, and between them a network of canals with many openings into the ring-canal.
Bibliography. 1. E. T. Browne, “Variation in Aurelia aurita,” Biometrika, i. (1901), pp. 90-108, 3 figs.; 2. “Scyphomedusae,” Fauna and Geogr. Maldives and Laccadives, ii., suppl. i. (1905), pp. 958-971, pl. xciv.; 3. O. Friedemann, “Untersuchungen über die postembryonale Entwicklung von Aurelia aurita,” Zeitschr. f. wiss. Zool. lxxi. (1902), pp. 227-266, pls. xii. xiii., 3 text-figs.; 4. W. Hein, “Untersuchungen über die Entwicklung von Aurelia aurita,” Zeitschr. wiss. Zool. lxvii. (1900), pp. 401-438, pls. xxiv. xxv., 5 text-figs.; 5. K. Kishinouye, “Some New Scyphomedusae of Japan,” Journ. Coll. Sci. Tokyo, xvii., No. 7 (1902), 17 pp., 2 pls.; 6. O. Maas, “Die Medusen” (Albatross Expedition), Mem. Mus. Comp. Zool. Harvard Coll. xxiii. 1 (1897), 92 pp., 15 pls., with explanations; 7. “Über Medusen aus dem Solenhofer Schiefer und der unteren Kreide der Karpathen,” Palaeontographica, xlviii. (1902), pp. 297-322, pls. xxii. xxiii., with explanations, and 9 text-figs.; 8. “Die Scyphomedusen der Siboga-Expedition,” Uitkomst. Siboga-Expeditie, xi. (1903), 91 pp., 12 pls., with explanations; “Méduses,” Result. Camp. Sci. Albert, Monaco, xxviii. (1904), 71 pp., 6 pls., with explanations; 10. “Médusen,” in Résultats du S. Y. Belgica (1906), 32 pp., 3 pls.; 11. “Die arktischen Medusen,” Fauna Arctica, iv. (1906), pp. 479-526; 12. O. Maas, “Über eine neue Medusengattung aus dem lithographischen Schiefer,” N.J.B. Mineral Geol. Palaeontol. (1906), ii. pp. 90-99, 4 text figs.; 13. W. Schewiakoff, “Beiträge zur Kenntnis des Acalephenauges,” Morph. Jahrb. xv. (1889), pp. 21-60 3 pls.; 14. E. Vanhöffen, “Die Akalephen der Plankton Expedition,” Ergebn. d. Plankt.-Exp. (1892), 28 pp., 5 pls.; 15. “Die acraspeden Medusen der deutschen Tiefsee-Expedition,” Deutsch. Tiefsee-Exped. “Valdivia,” iii. (1902), pp. 1-15, 8 pls. See also the general works cited in the article Hydrozoa and the bibliographies given in them. (E. A. M.)
SCYROS, a small rocky barren island in the Aegean Sea. Off the coast of Thessaly, containing a town of the same name. In 469 B.C. it was conquered by the Athenians under Cimon, and it was probably about this time that the legends arose which connect it with the Attic hero Theseus, who was said to have been treacherously slain and buried there. A mythic claim was thus formed to justify the Athenian attack, and Cimon brought back the bones of Theseus to Athens in triumph. The inhabitants of Scyros before the Athenian conquest were Dolopes (Thuc. 1. 98); but other accounts speak of Pelasgians or Carians as the earliest inhabitants. There was a sanctuary of Achilles on the island, and numerous traditions connect Scyros with that hero. He was concealed, disguised as a woman, in the palace of Lycomedes, king of the island, when his mother wished to keep him back from the Trojan War; he was discovered there by Odysseus, and gladly accompanied him to Troy. An entirely different cycle of legends relate the conquest of Scyros by Achilles. The actual worship on the island of a hero or god named Achilles, and the probable kinship of its inhabitants with a Thessalian people, whose hero Achilles also was, form the historical foundation of the legends. Scyros was left, along with Lemnos and Imbros, to the Athenians by the peace of Antalcides (387 B.C.). It was taken by Philip, and continued under Macedonian rule till 196, when the Romans restored it to Athens, in whose possession it remained throughout the Roman period. It was sacked by an army of Goths, Heruli and Peucini, in A.D. 269. The ancient city was situated on a lofty rocky peak, on the north-eastern coast, where the modern town of St George now stands. A temple of Athena, the chief goddess of Scyros, was on the shore near the town. The island has a small stream, called in ancient times Cephissus.
SCYTHAE (Gr. Σκύθαι), in Herodotus (iv. 1–142) and Hippocrates (De aere, 24 sqq.), a definite nation giving its name to Scythia (q.v.); in later writers a general term for the inhabitants of that country without distinction of race.
SCYTHE, an implement for mowing grass or reaping corn or grain, consisting of a curved steel blade fastened to a long wooden handle with a slight double curve from which project two small pieces by which the handle is held. The handle is
