DICTIONARY 365 DIDACTIC given to this magistrate was originally Magister Populi, but subsequently he was styled dictator, a name already familiar to the Latin states. The office was probably first created in B. C. 501, and the first dictator was Titus Larcius. The dictator was nominated by one of the consuls in pursuance of a decree of the Senate, whence the name, from the technical phrase, Dicere dictatorem. The nominator performed his duty at dead of night. Originally only one who had held the office of consul could be named dictator, but subsequently the office was thrown open to all, the first plebeian dic- tator being C. Marcius Rutilus, in B. C. 356. The dictator was named for six njonths only, but he seldom retained the office after the object for which he had been appointed was fulfilled. The office was abolished by law after the death of Caesar. DICTIONARY (from the Latin dictio, a saying, expression, word), a book con- taining the words, or subjects, which it treats, arranged in alphabetical order. It may be either a vocabulary, or a col- lection of the words in a language, with their definitions, or a special work on one or more branches of science or art prepared on the principle of alpha- betical arrangement, such as dictionaries of biography, law, music, medicine, etc. Among the dictionaries of the English language, the earliest seem to have been those of Barett (1573), and of BuUo- kar (1616). That of Dr. Johnson pub- lished in 1755 made an epoch in this department of literature. The first im- portant dictionary of the English lan- guage is that by Noah Webster (1828). It has been frequently republished, and in subsequent editions has almost entire- ly altered its character. The large American dictionary by Dr. Worcester was once a rival of Webster's. Dr. Ogilvie's English dictionary (based on Webster, and first published in 1847- 1850) was published in a remodeled and enlarged form (4 vols. 1881-1882, Chas. Annadale, LL.D., editor). Cassell's "Encyclopaedic Dictionary" is another extensive and useful work (1879-1888). An English dictionary "on historical principles," edited by J. A. H. Murray, LL. D., with the assistance of many schol- ars, is published at the Clarendon Press (London). The "Century Dictionary" (New York, 1889-1891) in six volumes, v/ith a supplementary "Cyclopaedia of Names," is a comprehensive and useful work. In 1885 appeared the "Standard Dictionary" (New York), which adopts the spelling reform system of the Ameri- can Philological Association. A revised edition appeared in 1915. The chief etymological dictionary of English words is that by Professor Skeat (1882); the chief French is that of Littre; German, that of Grimm. DICTOPHONE. An instrument made up of an ordinary telephone circuit to which is attached a granular carbon transmitter of a sensitiveness adequate to take up the words of persons convers- ing in a room so that they can be heard and recorded over the telephone. The transmitter is usually made small enough to be capable of concealment and the instrument has been in the main em- ployed by detectives for the gathering of evidence relating to persons under sus- picion. It is also coming into use for the reproduction of sounds in various parts of a hall and has also been in- stalled in the waiting room of railway stations, the announcer having his voice megaphoned by telephone receivers lo- cated in different parts of the building. DICTYNNA, a nymph of Crete, and one of the attendants of Diana. DICTYOGEN, a member of the sub- class Dictyogenae. DICTYOGEN.ffi, sub-class of mono- cotyledonous plants with leaves reticu- lated, often articulated with the stem; branches with the usual structure of endogens, but the rhizomes or under- ground stems have the woody matter dis- posed in a compact circle, or in wedges containing central cellular tissue, and often showing medullary processes. It comprises thi'ee orders, Dioscoreacese, or yam tribe ; Similacese, or the sarsaparilla lamily; and Trilliaeeag, or the trilliura family. DICYEMIDiE, a family of very lowly multicellular organisms, parasitic in habit. They are found in cuttlefishes, while related organisms known as Ortlio- nectida occur in a brittle-star and in a Nemertean worm. The largest species of the genus Dicyenia measures 5-7 milli- meters ; the smallest is 10 times less. DICYNODON, a genus of fossil rep- tiles occurring in a sandstone, supposed to be of Triassic age, in southern Africa and India. The principal remains yet found, the bones of the head, indicate a gigantic type between the lizards and turtles. Order, Ano77iodontia. DIDACTIC, or DIDACTICAL, a term applied to every species of writing, whether in verse or prose, the object of which is to teach or explain the rules or principles of any art or science. Thus, to this class of literature belong the writings of Aristotle on grammar, poetry and rhetoric; Longrlnus's "Trea-
