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support the claim, Lie thought to cement the alliance by making the Black Prince count of Flanders. This proposal was badly received by a large body of the people of Ghent, who were dissatisfied with their leader s somewhat arbitrary government. A popular tumult broke out with its usual
impulsiveness, and Artevelde was slain.ARTEVELDE, Philip van, son of the above, lived in retirement till 1381. Some years before that date enmity had again arisen between Count Louis of Flanders and the somewhat turbulent citizens of Ghent, who, under one Hyons, had exp lied the count s adherents, plundered his house, and slain several of his officers. Hyons died in 1379, and in 1381 the citizens^ under Peter van der Bosch (Dubois), were closely blockaded by the count. In this emergency Van der Bosch proposed that the son of the great Artevelde should be invited to take the direction of affairs, Philip accepted, at once entered on public life, and by some strong measures secured his power. The inhabitants of Bruges had at this time allied themselves with the count, and Artevelde resolved to punish them. He led out his forces quietly, and utterly defeated the army of the count, who escaped with difficulty. Bruges was plundered, and submitted to Artevelde. Next year the French, taking up the cause of Louis, invaded Flanders, and at Rosbecque completely routed the forces of Ghent. Many thousands were slain, and among them Artevelde himself. The brief but stirring life of this popular leader is admirably treated in Sir Henry Taylor's drama, Philip van Artevelde.
ARTHROPODA. The Aristotelian distinction of Malacostraca, or Crustaceans, and Entoma, or Insects, has been referred to by Agassiz as in reality more precise than Linnæus's last classification (1766), in which his Crustaceans form part of the Apterous group of insects. But whereas the Greek naturalist recognised the notchings which indicate annuli, somites, or body-rings, in Coleoptera and the other groups to which the class-name Insect is now restricted, and in Worms, under which he comprehended insect larvæ, several true Annelids, and intestinal worms (Scolecida), he failed to appreciate this as a feature common to the Malacostraca or Scleroderma, which he named on account of the character of their integument. Linnæus, on the other hand, saw that annulation was the most prominent common feature, and his Insecta, therefore, were a good natural group so long as embryology could throw no light on the affinities of the Cirripeds and parasitic Crustaceans—these two groups forming, together with the intestinal worms, molluscs, zoophytes, and lithophytes, the class Vermes. Cuvier (1829) includes in the third branch of his scheme, Animalia articulata, Annelids, Crustaceans, Arachnids, and Insects (the Myriapods being an order of this class). Latreille (1796) proposed a scheme in which the orders of the Insects (as now restricted) formed equivalent groups with the Crustaceans, Arachnids, and Myriapods, which now first appear as a distinct group, though still united with a section of the Crustaceans. Latreille further, in 1801, recognised the Cirripeds as intermediate between his Insecta and the Molluscs. Lamarck gave the value of classes to the Insects, the Arachnids (including therein the Thysanura and Myriapoda), the Crustaceans, and the Cirripeds. But he has no province answering to the Cuvierian Articulata, since these orders are, with Annelids, Conchifers (=Lamellibranchs), and Molluscs (=Odontophora),members of the “sensitive animals,” the Lernæans and other parasitic Crustaceans being an order of the Vermes, and therefore apathetic animals. De Blainville, still relying chiefly on external form, recognises four types in the sub-kingdom of the bilateral animals:—(Artiomorpha or Artiozoaria), of which the first is Osteozoaria (Vertebrates). The second, Entomozoaria (Articulates), includes: Class 1. Hexapoda, Insecta proprie sic dicta; 2. Octopoda, Arachnida; 3. Decapoda, Crustacea decapoda and Limulus; 4. Heteropoda, Squilla, Entomostraca, Epizoa; 5. Tetradeoapoda, Amphipoda and Isopoda; 6. Myriapoda; 7. Chætopoda, Annelides; 8. Apoda, Hirudo, Cestoidea, Ascaris. The third type, Malentozoaria, is intermediate between the Articulates and Molluscs, and embraces two classes: Nematopoda, Cirripeds; and Polyplaxiphora, the Chitons. The classification of which this forms a part is a compromise between the method of Cuvier, based on the recognition of distinct plans, and that of Ehrenberg, who sketched each group as departing from the common plan of the animal kingdom only by excess of development in one or other direction. The Articulata, viz., Insecta, , Crustacea (the Cirripeds and Epizoa being included), Annulata, and Somatotoma (the two latter making up all that are now known as Annelids), he distinguished from Molluscs by the isolation of their ganglia and their succession, those of the Molluscs being dispersed. Owen's Homogangliata, as equivalent to Articulata, is the expression of the same difference; his Insecta embrace two sub-orders, Myriapoda and Hexapoda, and the Annellata are placed between the Epizoa and Cirripeds. Milne-Edwards (1855) divides the Entomozoaria or Annellata into two groups,—(1.) Arthropoda, including Insects, Myriapods, Arachnids, and Crustaceans; and (2.) Vermes, including Annelids, Helminths, Turbellarians, Cestodes, and Rotifers. Siebold and Stannius (1845) made the Arthropods a primary division co-ordinate with Vermes, and united the Myriapods with the Crustaceans. Leuckart's Arthropoda comprise two classes, Crustacea and Insecta; the latter combining the orders, Myriapoda, Arachnida, and {{lang|la|Hexapoda. Fitzinger's Arthrozoa, or eminently motor animals, Crustaceans, Arachnoids, and Insects, contrast with the Dermatozoa or Molluscs, which are eminently sensitive. Von Baer's Articulata correspond to the Cuvierian group under the same designation, and like it represent a type of organisation, the longitudinal or bilaterally symmetrical, the organs being arranged with reference to the axial alimentary canal. The embryological system of Van Beneden (1855) rests upon the position of the vitellus relatively to the surface of the embryo, the Articulates being designated by him Epicotyledones or Epivitellians, the vitellus being received into the embryo on the dorsal or upper surface, while the vertebrates receive the yelk on the ventral or lower surface, and are therefore Hypocotyledones or Hypovitellians. As will be pointed out afterwards, this nomenclature is unfortunate, since the surfaces thus contrasted are identical, both being
the hæmal aspects of the body. It may further be remarked that the term Articulata is manifestly one which should be abandoned, since it is made to represent very different things, being used by Cuvier, Ehrenberg, and Owen to include the Annelids,—by Van Beneden, Vogt, and some more recent writers, to their exclusion. Neither is Arthrozoa, the Greek equivalent of Articulata, more commendable, Burmeister and Fitzinger using it with the same difference. But Arthropoda has varied only in the rank assigned to it, not in the area it represents; thus Milne-Edwards makes it a sub-division of the Annellata; Van Beneden, Siebold and Stannius, and Leuckart, a primary division of the animal kingdom. But as a general designation for those animals which are made up of nearly equivalent somatomes or somites is needed, Macleay's term Annulosa is, perhaps, the best, since it has never been used for two incommensurate groups. Leach, and later (1825) Latreille, proposed Condylopoda as the name of the group for which Arthropoda was afterwards devised. Custom has overborne the rule of priority, and the later is now the more common name. The classifications hitherto mentioned rest solely on an anatomical basis, those of Von Baer and Van Beneden deal-
