glands of the skin of the face in man, and is frequent in the skin of the dog. Many Acari are parasitic on marine and freshwater molluscs, and others are found on the feathers of birds and the hair of mammals. Others have a special faculty of consuming dry, powdery vegetable and animal refuse, and are liable to multiply in manufactured products of this nature, such as mouldy cheese. A species of Acarus is recorded as infesting a store of powdered strychnine and feeding on that drug, so poisonous to larger organisms. Reference to literature (40).
Authorities cited by numbers in the text.—1. Strauss-Dürckheim (as reported by MM. Riester and Sanson in an appendix to the sixth volume of the French translation of Meckel’s Anatomy, 1829); 2. Lankester, “Limulus an Arachnid,” Quart. Journ. Micr. Sci. vol. xxi. N.S., 1881; 3. Idem, “On the Skeletotrophic Tissues of Limulus, Scorpio and Mygale,” Quart. Journ. Micr. Sci. vol. xxiv. N.S., 1884; 4. Idem. Trans. Zool. Soc. vol. xi., 1883; 5. Lankester and A. G. Bourne, “Eyes of Limulus and Scorpio,” Quart. Journ. Micr. Sci. vol. xxiii. N.S., Jan. 1883; 6. Milne-Edwards, A., “Recherches sur l’anatomie des Limules,” Ann. Sci. Nat. 5th Series, Zoologie, vol. xvii., 1873; 7. Owen, Richard, “Anatomy of the King-Crab,” Trans. Linn. Soc. Lond., vol. xxviii., 1872; 8. Kishinouye, “Development of Limulus longispina,” Journal of the Science College of Japan, vol. v., 1892; 9. Brauer, “Development of Scorpion,” Zeitschrift für wiss. Zoologie, vol. lix., 1895; 10. Hansen, H. J., “Organs and Characters in Different Orders of Arachnida,” Entomol. Meddel. vol. iv. pp. 137-149; 11. Watase, “On the Morphology of the Compound Eyes of Arthropods,” Studies from the Biolog. Lab. Johns Hopkins University, vol. iv. pp 287-334; 12. Newport, George, “Nervous and Circulatory Systems in Myriapoda and Macrourous Arachnids,” Phil. Trans. Roy. Soc., 1843; 13. Lankester, “Coxal Glands of Limulus, Scorpio and Mygale,” Quart. Journ. Micr. Sci. vol. xxiv. N.S., 1884; 13a. W. Patten and A. P. Hazen, “Development of the Coxal Glands of Limulus,” Journ. of Morphology, vol. xvi., 1900; 13b. Bernard, “Coxal Glands of Scorpio,” Ann. and Mag. Nat. Hist. vol. xii., 1893, p. 55; 14. Benham, “Testis of Limulus,” Trans. Linn. Soc., 1882; 15. Lankester, “Mobility of the Spermatozoa of Limulus,” Quart. Journ. Micr. Sci. vol. xviii. N.S., 1878; 16. Korschelt and Heider, Entwickelungsgeschichte (Jena, 1892), ibique citata; 17. Laurie, M., “The Embryology of a Scorpion,” Quart. Journ. Micr. Sci. vol. xxxi. N.S., 1890, and “On Development of Scorpio fulvipes,” ibid. vol. xxxii., 1891; 18. Lankester (Homoplasy and Homogeny), “On the Use of the term Homology in Modern Zoology,” Ann. and Mag. Nat. Hist., 1870; 19. Idem, “Degeneration, a Chapter in Darwinism,” 1878, reprinted in the Advancement of Science (Macmillan, 1890); 20. Idem, “Limulus an Arachnid,” Q. J. Micr. Sci. vol. xxi. N.S.; 21. Claus, “Degeneration of the Acari and Classification of Arthropoda,” Anzeiger d. k. k. Akad. Wissen. Wien, 1885; see also Ann. and Mag. Nat. Hist. (5) vol. xvii., 1886, p. 364, and vol. xix. p. 225; 22. Lindström, G., “Researches on the Visual Organs of the Trilobites,” K. Svenska Vet. Akad. Handl. xxxiv. No. 8, pp. 1-86, Pls. i.-vi., 1901; 22*. Zittel, American edition of his Palaeontology (the Macmillan Co., New York), where ample references to the literature of Trilobitae and Eurypteridae will be found; also references to literature of fossil Scorpions and Spiders; 23. Hoek, “Report on the Pycnogonida,” Challenger Expedition Reports, 1881; Meinert, “Pycnogonida of the Danish Ingolf Expedition,” vol. iii., 1899; Morgan, “Embryology and Phylogeny of the Pycnogonids,” Biol. Lab. Baltimore, vol. v., 1891; 24. Bourne, A. G., “The Reputed Suicide of the Scorpion,” Proc. Roy. Soc. vol. xlii. pp. 17-22; 25. Lankester, “Notes on some Habits of Scorpions,” Journ. Linn. Soc. Zool. vol. xvi. p. 455, 1882; 26. Huxley, “Pharynx of Scorpion,” Quart. Journ. Micr. Sci. vol. viii. (old series), 1860, p. 250; 27. Pocock, “How and Why Scorpions hiss,” Natural Science, vol. ix., 1896; cf. idem, “Stridulating Organs of Spiders,” Ann. and Mag. Nat. Hist. (6), xvi. pp. 230-233; 28. Kraepelin, Das Thierreich (Scorpiones et Pedipalpi) (Berlin, 1899); Peters, “Eine neue Eintheilung der Skorpione,” Mon. Akad. Wiss. Berlin, 1861; Pocock, “Classification of Scorpions,” Ann. and Mag. Nat. Hist. (6) xii., 1893; Thorell and Lindström, “On a Silurian Scorpion,” Köngl. Svens. Vet. Akad. Handl. xxi. No. 9, 1885; 29. Cambridge, O. P., “A New Family (Tartarides) and Genus of Thelyphonidea,” Ann. and Mag. Nat. Hist. (4) x., 1872, p. 413; Cook, “Hubbardia, a New Genus of Pedipalpi,” Proc. Entom. Soc. Washington, vol. iv., 1899; Thorell, “Tartarides, &c.” Ann. Mus. Genova, vol. xxvii., 1889; 30. M'Cook, American Spiders and their Spinning Work (3 vols.; Philadelphia, 1889–1893); 31. Peckham, “On Sexual Selection in Spiders,” Occasional Papers Nat. Hist. Soc. Wisconsin, vol. i. pp. 1-113, 1889; 32. Moggridge, Harvesting Ants and Trap-Door Spiders (1873); 33. Bertkau, Ph., Arch. f. Naturgesch. vol. xlviii. pp. 316-362; Idem, same journal, 1875, p. 235, and 1878, p. 351; Cambridge, O. P., “Araneidea” in Biologia Centr. Americana, vols. i. and ii. (London, 1899); Keyserling, Spinnen Amerikas (Nuremberg, 1880–1892); Pocock, “Liphistius and the Classification of Spiders,” Ann. and Mag. Nat. Hist. (6) x., 1892; Simon, Hist. nat. des Araignées, vols. i. and ii., 1892, 1897; Wagner, “L’Industrie des Araneína,” Mém. Acad. St-Pétersbourg; Idem, “La Mue des Araignées,” Ann. Sci. Nat. vol. vi.; 34. Grassi, G. B. “Intorno ad un nuovo Aracnide artrogastro (Koenenia mirabilis) &c.” Boll. Soc. Ent. Ital. vol. xviii., 1886; 35. H. J. Hansen and Sörensen, “The Order Palpigradi, Thorell (Koenenia), and its Relationships with other Arachnida,” Ent. Tidskr. vol. xviii. pp. 233-240, 1898; Kraepelin, Das Thierreich (Berlin, 1901); 36. Bernard. “Compar. Morphol. of the Galeodidae,” Trans. Linn. Soc. Zool. vol. vi., 1896, ibique citata; Dufour, “Galeodes,” Mém. prés. Acad. Sci. Paris, vol. xvii., 1862; Kraepelin, Das Thierreich (Berlin, 1901); Pocock, “Taxonomy of Solifugae,” Ann. and Mag. Nat. Hist. vol. xx.; 37. Balzan, “Voyage au Vénézuela (Pseudoscorpiones),” Ann. Soc. Entom. France, 1891, pp. 497-522; 38. Guérin-Méneville, Rev. Zool., 1838, p. 11; Karsch, “Ueber Cryptostemma Guer.” Berliner entom. Zeitschrift, xxxviii. pp. 25-32, 1892; Thorell, “On an apparently new Arachnid belonging to the family Cryptostemmidae,” Westv. Bihang Svenska Vet. Akad. Handligar, vol. xvii. No. 9, 1892; 39. Hansen and Sörensen, On Two Orders of Arachnida (Cambridge, 1904); Sörensen, “Opiliones laniatores,” Nat. Tidskr. (3) vol. xiv., 1884; Thorell, “Opilioni,” Ann. Mus. Genova, vol. viii., 1876; 40. Berlese, “Acari, &c., in Italia reperta” (Padova, 1892); Canestrini, Acarofauna Italiana (Padova, 1885); Canestrini and Kramer, “Demodicidae and Sarcoptidae” in Das Thierreich (Berlin, 1899); Michael, “British Oribatidae,” Ray Soc.; Idem, “Oribatidae” in Das Thierreich (Berlin, 1898); Idem, “Progress and Present State of Knowledge of Acari,” Journ. Roy. Micr. Soc., 1894; Nalepa, “Phytoptidae,” Das Thierreich (Berlin, 1898); Trouessart, “Classification des Acariens,” Rev. Sci. Nat. de l’ouest. p. 289, 1892; Wagner, Embryonal Entwick, von Ixodes (St Petersburg, 1893); 41. Bertkau, Ph., “Coxaldrusen der Arachniden,” Sitzb. Niederl. Gesellsch., 1885; 42. Patten, W., “Brain and Sense Organs of Limulus,” Quart. Journ. Mic. Sci. vol. xxxv., 1894; see also his “Origin of Vertebrates from Arachnids,” ibid. vol. xxxi.
Authorities not cited by numbers in the text:—
Lung-books:—Berteaux, “Le Poumon des Arachnides,” La Cellule, vol. v. 1891; Jawarowski, “Die Entwick. d. sogen. Lunge bei der Arachniden,” Zeitsch. wiss. Zool. vol. lviii., 1894; Macleod, “Recherches sur la structure et la signification de l’appareil respiratoire des Arachnides,” Arch. d. Biologie. vol. v., 1884; Schneider, A., “Mélanges arachnologiques,” in Tablettes zoologiques, vol. ii. p. 135, 1892; Simmons, “Development of Lung in Spiders,” Amer. Journ. Science, vol. xlviii., 1894. Coxal Glands:—Bertkau, “Ueber die Coxaldrusen der Arachniden,” Sitzb. d. Niederl. Gesellsch., 1885; Loman, “Altes und neues über das Nephridium (die Coxaldrüse) der Arachniden,” Bÿd. tot de Dierkunde, vol. xiv., 1887; Macleod, “Glande coxale chez les Galéodes,” Bull. Acad. Belg. (3) vol. viii., 1884; Pelseneer, “On the Coxal Glands of Mygale,” Proc. Zool. Soc., 1885; Tower, “The External Opening of the brick-red Glands of Limulus,” Zool. Anzeiger, vol. xviii. p. 471, 1895. Ento-sternite:—Schimkewitsch, “Bau und Entwick. des Endosternites der Arachniden,” Zool. Jahrb., Anal. Abtheil., vol. viii., 1894. Embryology:—Balfour, “Development of the Araneina,” Q. J. Micr. Sci. vol. xx., 1880; Kingsley, “The Embryology of Limulus,” Journ. Morphology, vols. vii. and viii.; Kishinouye, “Development of Araneina,” Journ. Coll. Sci. Univ. of Japan, vol. iv., 1890; Locy, “Development of Agelena,” Bull. Mus. Harvard, vol. xii., 1885; Metchnikoff, “Embryologie d. Scorpion,” Zeit. wiss. Zool. vol. xxi., 1871; Idem, “Embryol. Chelifer,” Zeit. wiss. Zool. vol. xxi., 1871; Schimkewitsch, “Développement des Araignées,” Archives d. Biologie, vol. vi. 1887. Sense organs:—Bertkau, “Sinnesorgane der Spinnen,” Arch. f. mikros. Anat. vol. xxvii. p. 589, 1886; Graber, “Unicorneale Tracheaten Auge,” Arch. f. mikr. Anat. vol. xvii., 1879; Grenacher, Gehörorgane der Arthropoden (Göttingen, 1879); Kishinouye, “Lateral Eyes of Spiders,” Zool. Anz. vol. xiv. p. 381, 1891; Purcell, “Phalangiden Augen,” Zool. Anzeiger, vol. xv. p. 461.
General works on Arachnida:—Blanchard, “Les Arachnides” in L’Organisation du regne animal; Gaubert, “Recherches sur les Arachnides,” Ann. Sci. Nat. (7) vol. xiii., 1892; Koch, C., Die Arachniden (16 vols., Nuremberg, 1831–1848); Koch, Keyserling and Sörensen, Die Arachniden Australiens (Nuremberg, 1871–1890); Pocock, Arachnida of British India (London, 1900); Idem, “On African Arachnida,” in Proc. Zool. Soc. and Ann. and Mag. Nat. Hist., 1897–1900; Simon, Les Arachnides de la France (7 vols., Paris, 1874–1881); Thorell, “Arachnida from the Oriental Region,” Ann. Mus. Genova, 1877–1899. (E. R. L.)
ARAD, or Ó-Arad, a town of Hungary, capital of the county of the same name, 159 m. S.E. of Budapest by rail. Pop. (1900) 53,903. It is situated on the right bank of the river Maros, and consists of the inner town and five suburbs. Arad is a modern-built town, and contains many handsome private and public buildings, including a cathedral. It is the seat of a Greek-Orthodox bishop, and possesses a Greek-Orthodox theological seminary, two training schools for teachers—one Hungarian, and the other Rumanian—and a conservatoire for music. The town played an important part in the Hungarian revolution of 1848–49, and possesses a museum containing relics of this war of independence. One of the public squares contains a martyrs’ monument, erected in memory of the thirteen Hungarian generals shot here on the 6th of October 1849, by order of the Austrian general Haynau. It consists of a colossal figure of
