HYPOCOTYL. 408 HYPOSTASIS. HY'POCOTYL (abbreviation of hypocotyle- doiiotin. Iiom (;k. vr6, hypo, under + kotuXjjSuu', kolyliilun. cotyledon, from kotv>ii, kotylc, socket). In seed-plants, tlic a.xis of the embryo below the cotyledons. This axis has been variously called 'railiclo' and 'eaulicle,' but since it lias peculiar powers which do not belong to ordinary root and stem structures, it has received a distinctive name. Sec Kmiirvo. HYPOCRITE, The. A play by Isaac Bicker- stalle, produced in 1708, and founded on Cibbcr'8 on-Jiirur, which, in turn, was taken from the Tnrtnfr of >Tolii^re. HY POCY'CLOID. See Cycloid. HYPODER'MIC MEDICATION (from Gk. wr(S, hfijiu. miller + iipiJM. tkrmu. skin). Intro- duction of medicines beneath the skin, with a hy- podermic syringe. This method is often prefer- able to that of giving them by the mouth. The stomach is sometimes in a condition which will not bear the presence of drugs, particularly nar- cotics, and these are the agents which are most frequently administered hypodermieally. A small graduated glass syringe attached to a slender hollow needle, cut ofT obliquely so that its sharp- ened extremity may easily be made to pierce the skin, is used. The medicine may be thrown in just beneath the skin, or the point of the syringe is thrust into the body of a muscle. The wound- ing of bloodvessels or ner'es should be carefully avoided, and therefore the operation should not be undertaken except by a physician or a trained luirsc. Local pains may generally be more suc- cessfully treated in this manner than by the common method. In some ca.ses an anaesthetic may, however, be preferable. It is usual to make a .special preparation of the drug which is to be introduced. The syringe must be completely filled when used, as the introduction of an air- bubble into a vein might be attended with dan- ger. All instruments and drugs used should be thoroughly sterilized. The hypodermic syringe .should be used with great caution, and never by the patient. HYPODER'MIS (Neo-Lat, from Gk. irro. iep/jic, underskin, from v-i, hypo, under -f- iipfia, drrma, skin). In plants, a layer of cells lieneath the epidermis. An archesporial cell is said to be hypodermal in origin when it arises immediately beneath the epidermis. Tissues bordering directly upon the epidermis are called hypnrlrrmiil. HYPOGYNY, ht-p6j1-nl (from Gk. M,hypo, under -{■ yvv>/. fiync, woman). The condition in a flower in which the sepals, petals, and stamens arise from beneath the ova^^■. As a consequence, the ovary is .seen inside of the flower, and is often spoken of as 'superior.' The contrasting term is 'epigj'ny' (q.v.). Hypogj-nous flowers are con- sidered to he more primitive in character than epigynnus tlmvers. Sec Flower. HY'PONASTY (from Gk. xnrb. hypo, under + vaarSc, nastos, close-pressed, from vi'innetv, nasscin, to pack closely). A term applied by I)e Vries to the occurrence of greater growth upon the under side of a doraivcntral organ, which produces therefore an upward curvature. This may be due to internal or external causes. Tt is the common condition of young leaves and flower parts when in the bud. The correlative term is epinasty. See Gbowth (in Plants). HY PONI'TRITES. See Hvponitbous Acid. HYPONI'TROUS ACID, li,XA. An acid which may be ohtaiiicd In dilute aqueous .solu- tion, or in the form of its salts, but which has not been isolated in a concentrated state. Its salts are termed hyponilrilcn. It may be ob- tained by allowing sodium amalgam to act upon barium nitrite, neutralizing the resulting solu- tion with acetic acid, precipitating with silver nitrate, and' decomposing with hydrochloric acid the silver hyponilrlte thus obtained. Silver hyponltrite. Ag.XjO., explodes if heated to a moderately high temperature. The solution of free hyponitrous acid decomposes, on heating, into nitrous oxide ("laughing gas') and water. HY POPHOS'PHITES. See Hypopiiospiio- KOVS .l 111. HY POPHOS'PHOROUS ACID, II.PO,. A crystalline inm]i(iuMil llial mclls at about 17.5°C. and is readily traiisfiirnicd into ordinary phos- phoric acid. It may be obtained by boiling caustic potash with ])hosph(irus, subsequently adding sulphuric acid, concentrating the solution by evaporation and allowing it to crystallize in the cold. The salts of hypophosphorous acid are termed hypophosphltes, those of iron, calcium, sodium, and potassium being extensively used in medicine, and often forming ingredients of patent medicines which are claimed to be valua- ble remedies for tuberculosis. Most such prepa- rations are worthless, being mixtures of the hypophosphltes of two or more metals, the sev- eral ingredients of which may counteract one another; and some such mixtures are positively harmful. On the other hand, if prescribed separately, in moderate doses, by a competent physician, the hypophosphltes often constitute valuable therapeutic agents, inasmuch as they have the efTeet of improving nutrition and re- lieving some of the symptoms of phthisis. The hypophosphite of potassiimi may be used as an expectorant in chronic bronchitis. The ofTiclnal syrup of hypophosphltes contains several hj-po- phosphites. a considerable amount of free hypo- phosphorous acid, and often some iron. HYPOS'TASIS (Xeo-Lat., from Gk. {rn-SaTamc, hypostasis: subsislence, from v-dr^Tarnr , hypostn- tos, substantial, from vil/iaravai, hyphistanai, to stand under, from Inri, hypo, under + larivai histanai, to stand). A term of Greek theology, variouslv employed before the fourth century, but at last technically used to denote personal distinctions in the Godhead. The Council of Nica-a (325) did not clearly distinguish be- tween hypostasis and ousia (substance and es- sence ) , and a cont roversy followed. ( See HoMOOU- siox.) The same uncertainty appears in the West as late as Augustine, who confes.ses that he does not understand the difl'ereiiee between the two Greek words (De Trinilate. v. 8, 10). But gradually the two words were difTercntiated. and hypostasis came to be used exclusively for the personality of Father, Son, or Holy Spirit. It was thus interpreted as being equivalent to pros- opon, which the Latin rendered by persona, whence our word 'person.' The fully developed trinitarian dogma asserts one essence, or sub- stance (ousia), and three persons (hypostasis) in the Godhead. This has remained the orthodox faith of the Church. Consult: the Histories of Doctrint, by Hamack, vol. iv. (London, 1898) ;
