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560 EMBRACERY EMBRYOLOGY of the cultivator. By the common law, if the estate of a tenant for life or at will is terminated unexpectedly without his volition or default, the emblements belong to such tenant or his representatives ; but if terminated by the act of the tenant himself, or if a tenant for years sows crops which do not mature within the Lie of the lease, the emblements pass with the land to the landlord ; for the law does not re- lieve a man from the consequences of his own voluntary act. EMBRACERY, an attempt to influence a juror by any unlawful consideration, as by private influence or by bribery. This was a criminal offence at common law, and the punishment has been prescribed by different statutes in England and the United States. The offence consists in the attempt, and it is not necessary that it should be successful. EMBRUN (anc. Eburodunum), a fortified town of Dauphiny, France, in the department of Hautes-Alpes, 19 m. E. by N. of Gap ; pop. in 1866, 4,736. It is a dreary-looking town of great antiquity, built upon a rock at whose foot flows the Durance. It contains a cathe- dral with a fine Romanesque tower, and near the former episcopal palace, which is used as a barrack, rises a quaint tower of ancient masonry known as la tour brune. The fortress is of the fourth rank, and is separated by a ditch from the mountain behind it. The prin- cipal manufactures are of woollen and linen goods. The bishops (subsequently archbishops) of Embrun are traced back to the days of Con- stantine the Great, and were endowed by Con- rad II. with princely power over a large part of Dauphiny. A portion of their archives was carried off during the wars of the league, and is now in the public library of Cambridge, England. Embrun was successively sacked by the Vandals, Huns, Saxons, and Moors ; in 1573 it was taken by the Protestants, who razed the citadel ; and in 1692 it was devas- tated by the duke of Savoy. Louis XIV. built the chateau of Mont-Dauphin in the vicinity. EMBRYOLOGY, the study of the mode of for- mation and development of the animal foetus. The progress of our knowledge on this subject has been marked by several well defined epochs, corresponding with the successive discoveries of as many different investigators. Though many important facts bearing upon embryol- ogy were known to the earlier anatomists and physiologists, they were often misinterpreted, and their true relations consequently mistaken. Aristotle and his followers recognized three different modes of generation as occurring among animals, viz. : oviparous, viviparous, and spontaneous generation. Oviparous genera- tion was that form in which the female parent produced eggs, from which the young were hatched, as in most fishes, reptiles, and birds; viviparous generation was that in which the young were discharged alive and fully formed from the body of the parent, as in quadrupeds and the human species; while spontaneous or equivocal generation was that in which certain animals of a low order, such as worms, insects, parasites, maggots, &c., were supposed to be produced spontaneously, without parents, from the soil, the water, or decaying animal and vegetable substances. By the progress of in- vestigation, however, the last mode of genera- tion was shown to be much less frequent in its occurrence than Aristotle had supposed. The first advance in this direction was made in the latter part of the 17th century, when Redi, an Italian naturalist, studied with care the genera- tion and metamorphoses of insects, showing that many worms and maggots, instead of be- ing produced without parents, were in reality hatched from eggs laid by perfect insects, and that they afterward became developed by the process of growth into forms similar to their parents. He also in 1684 showed that most parasitic animals were provided with sexual organs, and produced their young in the same manner with other and larger species. Vallis- nieri soon afterward (1700) extended the ob- servations of Redi, and applied the same con- clusions to other species of insects, and to the parasites inhabiting vegetables. In this way the number of species in which spontaneous generation was regarded as possible or probable gradually diminished, as zoological science be- came more extended and more accurate ; until, in 1837, Schultze demonstrated, by his experi- ments upon the infusoria, that even these mi- croscopic animalcules are never produced in situations where their germs neither existed be- fore nor could gain access from without. Sub- sequently it was generally acknowledged by physiologists that spontaneous generation was a thing unknown in nature, and that the sup- posed instances of its occurrence were only cases in which the real process of generation had not been sufficiently investigated. The discussion on this point has again been taken up since 1858, and it has been maintained by Pouchet, Bastian, and others, that spontaneous generation may and does take place in the case of the lowest and most imperfectly known forms of infusoria, such as vibrio, ~bacterium, morias, and spirillum. Their experiments, however, are by no means regarded as conclusive by physiologists in general, a large proportion of whom consider the apparent uncertainty of origin as dependent on our imperfect acquain- tance with the natural history and develop- ment of these minute forms of infusorial life. The distinction between oviparous and vivipa- rous animals was supposed by the ancients to indicate a fundamental difference in their mode of generation. In oviparous animals the eggs were known to be produced by the female and fecundated by the male, after which the young were hatched from them by incubation. In the viviparous species the embryo was thought to be produced by a mixture of the male sperm with the fluids of the female generative organs ; I some thinking that the material for the body of the embryo was supplied by the menstrual