DICYNODON. 225 DIDEROT. to have been evolved. Relatives uf Dieynodoii that do not liave tlie prominent incisor tusks are found in the Tiiassic heds of Scotland. See StEGOCEPH.L1. ; TlIEROMOBPHA. DIDACHE, did'a-kf. See Teacui.ng of the TwEi.x E Aros 1 i.KS. DIDACTIC POETRY. That kind of j.octry wbieli aims, or seems to aim, at instructiofi as its object, making pleasure entirely subservient to this. It has been disputed whether the exist- ence of a kind of poetry especially entitled to the name didactic consists with the very nature and object of the poetic art. For it is held that to point out instruction as the peculiar object of one kind of poetry is to overlook the high aim of all poetry, and that a poem may be in the highest sense ethical without any obvious aim at instruction. The drama of Sliakespeare has an immense ethical or moral value, but it is not didactic. Examples of purely didactic poetry are Vergil's Georflics, Horace's Ars Poelica, Pope's l-.'ssin/ iin Criticism and Essay on Man. DIDAPPER, di'daper. Beav. A poor-spirit- ed weakling in pursuit of Fanny in Fielding's Joseph .l)tdreics. DIDEL'PHIA (Xeo-Lat.. from Gk. Si-, di-, double -f SeXtpvi; delphys, womb), or Meta- THEKIA. The second of the three great subclasses of mammals (q.v. ), containing only the single order Marsupialia (q.v.). The name is derived from the 'double' condition of the womb in the female, where the uterine dilatations of the ovi- ducts continue through life distinct from each other. There are also two vaginse. each with its own opening into the cloaca, into which the rec- tum and ureters likewise open. There is no well- developed placenta, and it is generally entirely wanting, though it is now thought that its ab- sence is a secondary condition and not primitive, as it has been shown to be present in the early stages of development in the bandicoots {Per- ameles). DIDEROT, de'd'-r<y. Dexis (171.3-84). One of the most brilliant, versatile, and prolific writers of the French 'philosophic' generation. He was bom at Langres, October 5, 171.3. and was educated by the .Jesuits. He declined to study medicine or law. quarreled with his family, and eked out a meagre livelihood in young man- hood by literary hack work and teaching mathe- matics. After several discreditable boheniian adventures, he married (1743). and became defi- nitely estranged from his father. In this year he published translations of Stanyan's Histor;/ of Greece, and in 174G a translation of James's Dirlionnri/ of .Medicine, with an /iTs.wi' sur le nie- rile et la rertn. a paraphrase of Shaftesbury. The Penwps philosophiqiies of this year was his first independent work, and is said to have been in- spired by a caprice of his mistress, iladame de Puisienx, who certainly prompted his anony- mous and most indecent novel, I.es bijoux hi- disrrets (1748), of which he is reported to have said later that he "would cut off an arm not to have written it," though he was never squeam- ish in fiction. Diderot's first work of philosophic importance is the Leftrr siir Ie.vas venal as well as corrupt. The EncjelnpMic counts twenty-eight volumes (17.51-72), with a six-vol- ume supplement (1776-771 and two volumes of tables (1780). It was not primarily or chiefly revolutionary, but practical. . branches of science, manufacture, and agriculture were treat- ed with great fullness. It is only occasionally, and then often by mocking insinuation rather than direct attack, that it touches religion or morals, in which it has no consistent theory to uphold. The attacks on legal abuses and feudal survivals are quite as marked a feature. The work was greeted with immense enthusiasm and was hardly in print before it was out of it. The last sets brought the price of a rarity, and it was several times reprinted. Diderot " had during brief intervals of repose in this herculean work found opportunity to compose two plays— Le fils naturel (17571 and Le pere d^; famille (1758) — that mark the beginning of the modern domestic drama, and by his critical Paradoxe sur le come- dicn had great influence on Lessing, and so on the German stage. The French classic tragedy had confined itself to 'noble' themes. Diderot took his tragic situations from every-day middle-class life. To this period belongs also an essay on painting in the Eneyclopedie, which Goethe trans- lated, adding a luminous commentary; his post- humously published novel. La Rciigieuse (1759) ; the eccentric Jacques le fataliste (1773), also posthumous; and the yet more eccentric Le neveu de I'ameau. which first appeared in print in a translation by Goethe (1805). Diderot wrote also three short stories and nine Salons, critiques beginning in 175!) on the annual exhibition of painting, and unsurpassed in their untechnical and suggestive freshness. In 1773 Diderot, who had received but .$000 a year for his work on the EncyclopMie, felt constrained to sell his library. It was pur- chased by Catharine II., and presented to him as salaried caretaker. He went to Saint Petersburg to thank the Empress, and spent some months there in her intimate society. He re- turned in 1774 and passed his last decade in ephemeral writing and conversations that left lasting impressions. In talk his contemporaries thought him unrivaled. "He who knows Diderot in his writings only," said Marmontel, "does not know him at all." Ho worked and talked with disinterested enthusiasm, greeting the mention of a collected edition of his writings with laughter.
