DEMAND IN RECONVENTION. In Louisiana, this term is used to signify the demand which the defendant institutes in consequence of that which the plaintiff has brought against him. Code of Pr. art. 374. Vide Cross action.

DEFANDANT, practice. The plaintiff or party who brings a real action, is called the demandant. Co. Litt. 127; 1 Com. Dig. 85.

DEMENCY, dementia, med. jur. A defect, hebetude, or imbecility of the under standing, general or partial, but confined to individual faculties of the mind, particularly those concerned in associating and comparing ideas, whence proceeds great, confusion and incapacity in arranging the thoughts. 1 Chit. Med. Jur. 351; Cyclop. Practical Med. tit. Insanity; Ray, Med. Jur. ch. 9; 1 -Beck's Med. Jur. 547.

2. Demency is attended with a general enfeeblement of the moral and intellectual faculties, consequence of age or disease, which were originally well developed and sound. It is characterised by forgetfulness of the past; indifference to the present and future, and a childish disposition. It differs from idiocy and imbecility. In these latter, the powers of the mind were never possessed, while in demency, they have been lost.

3. Demency may also be distinguished from mania, with which it is sometimes confounded. In the former, the mind has lost its strength, and thereby the reasoning faculty is impaired; while in the latter, the madness arises from an exaltation of vital power, or from a morbid excess of activity.

4. Demency is divided into acute and chronic. The former is a consequence of temporary errors of regimen, fevers, hemorrhages, &c., and is susceptible of cure the latter, or chronic demency, may succeed mania, apoplexy, epilepsy, masturbation, and drunkenness, but is generally that incurable decay of the mind which occurs in old age.

5. When demency has been fully established in its last stages, the acts of the individual of a civil nature will be void, because the party had no consenting mind. Vide Contracts; Wills; 2 Phillim. R. 449. Having no legal will or intention, he cannot of course commit a crime. Vide Insanity; Mania.

DEMESNE, Eng. law. The name given to that portion of the Iands of a manor which the lord retained in his own hands for the use of himself and family. These lands were called terra dominicales or demesne lands, because they were occupied by the lord, or dominus manerii, and his servants, &c. 2 Bl. Com. 90. Vide Ancient Demesne; Demesne as of fee; and Soil assault demesne.

DEMESNE AS OF FEE. A man is said to be seised in his demesne as of fee of a corporeal inheritance, because he has a property dominicum or demesne in the thing itself. 2 Bl. Com. 106. But when he has no dominion in the thing itself, as in the case of an incorporeal hereditament, he is said to be seised as of fee, and not in his demesne as of fee. Liit. s. 10; 17 S. & R. 196; Jones on Land Titles, i66.

2. Formerly it was the practice in an action on the case, e. g. for a nuisance to real estate, to aver in the declaration the seisin of the plaintiff in demesne as of fee; and this is still necessary, in order to estop the record with the land; so that it may run with or attend the title. Arch. Civ. Pl. 104; Co. Ent. 9, pl. 8 Lill. Ent. 62; 1 Saund. Rep. 346; Willes, Rep. 508. But such an action may be maintained on the possession as well as on the seisin, although the effect of the record in this case upon the title would not be the same. Steph. on Pl. 322 Arch. Dig. 104; 1 Lutw. 12; 2 Mod. 71; 4 T. R. 718; 2 Saund. 1 Arch. Dig. 105; Cro. Car. 500. 575

DEMIDIETAS. This word is used in ancient records for a moiety, or one half. DEMIES. In some universities and colleges this term is synonymous with scholars. Boyle on Charities, 129.