THRIFT. 256 THROAT. it is often planted in gardens as a border, but it must be renewed every two or three 3'ears, the smallest rootless sets growing, however, with great readiness in the moist weather of spring. A number of other species, for instance, Arnieria elongata, Armcria plantagiiieu, are planted as ornamentals. THRIPS (Lat., from Gk. 8fil^, wood-worm). Any one of the minute insects of the order Thy- sanoptera. They are slender insects with four wings, which are also very slender and short, perfectly transparent, and without veins. They are fringed with long, delicate hairs, and when at rest lie along the back of the abdomen. The metamorphosis is incomplete, and the mouth- parts function in sucking, but are intermediate between true biting and true sucking mouth- parts. The feet bear each a little bladder-like vesicle at the tip, from which an old name of the order (Physapoda) was derived. Thrips are found in flowers, and do some damage to the es- sential organs. They also occur upon the leaves of plants, and one species damages onions ( see Onion Insects) and tobacco. Another species (Limothrips pouphagiis) works in the joints of timothy grass, causing the heads premature!}' to turn yellow and die. Some species have been ob- served feeding upon other insects and others un- doubtedly liave some beneficial ell'ect as fertilizers of flowers. Parthenogenesis sometimes occurs with these insects. Rather more tlian thirty species occur in the United States. The name 'thrips' has been erroneously applied by vine-growers to some of the leaf-hoppers of the family Jassidce. Consult Hinds, Contribution to a Monograph of the Insects of the Order Thysanoptcra Inhabit- ing X or 111 America (Washington, 1902). THROAT (AS. protii, OHG. drozza, Ger. 'Drossel, throat ; connected with 1IHG. strozze, throat, Ger. strotzot, to swell, Eng. strut). Af- fections OF THE. The throat includes those structures lying behind and below the anterior pillars of the fauces. In the common accepta- tion of the term it also means the anterior por- tion of the neck, containing the windpipe, gullet, and a number of large blood-vessels and nerves. The throat ma.v be divided anatomically into the pharj'nx and the larynx, the latter being the upper part of the windpipe and the principal organ of the voice. Into the pharvn.K open the nasal passages and the Eustachian tubes. The en- trance to the pliaryn.x is nearly surrounded by a ring of lymphoid tissue, comprising the faucial, lingual, and pharyngeal tonsils. The first of these are usually known as 'the tonsils, are al- ways present, and often enlarged, and are situ- ated at the sides of the fauces between the an- terior and posterior pillars. The lingual tonsil, when it exists, lies between the base of the tongue and the epiglottis. The pharyngeal ton- sils, more often referred to as adenoid growths, spring from the roof and sides of the pharvmgeal vault. They are often present in children and when in any amount constitute a pathological condition, giving rise to obstructed nasal breath- ing, nasal catarrh, and general poor health. Any or all of these structures may be involved in diseases of the throat, and expert examination of them is often necessary. Inspection is usually conducted by light reflected into the throat from a head mirror, a circular, concave reflector pierced with a hole for vision. The light is projected through the open mouth upon the back of the throat. I'rom this point the rays of light may be reflected bj' means of a small mirror introduced into the pharynx either downward to examine the larynx (laiyngoscopy) or upward to inspect the posterior nares and the vault of the pharynx ( rhinoscopy ) , the tongue being mean- while held out or depressed. In direct examina- tion the tonsils, soft palate, uvula, posterior wall of the phaiynx, and often the top of the epiglottis may be seen. Larj'ngoscopy shows the wliole of the epiglottis, the root of the tongue, lingual tonsil, the true and false vocal cords, the opening of the glottis, and even the bifurcation of the trachea. The throat is lined with mucous membrane, plentifully sujiplied with blood-vessels, ghmds, and nerves, and is often the seat of acute or chronic catarrhal inflammation. Acute inflam- mation of either the pharpix or laryn.x is due to e.xposure, sudden change of temperature, the inhalation of dust, steam, or irritating vapors, indigestion and constipation, and certain diseases such as rheumatism, gout, and tuberculosis. Chronic catarrh arises also from the causes named wlien long continued, and may be due to excessive iise or straining of the voice. Spe- cific inflammations of the throat accompanying scarlatina and diphtheria are described under these titles. Catarrhal inflammation of the throat is marked by a sense of dryness, or of a foreign body in the pljarjaix, a slight but annoy- ing cough, and the expectoration of viscid, tena- cious mucus, sometimes tinged with blood. The voice is hoarse, easily fatigued, or entirely ab- sent. In the treatment of catarrrhal conditions in this region, alkaline and antiseptic douches are given to remove the mucous accumulations, and stimulating and astringent applications, svich as tannin, iron, and nitrate of silver, used to reduce congestion and restore the membrane to its normal action. Naso-pharyngeal catarrh is frequently caused by intra^-nasal abnormalities and may as often be remedied by restoring natural respiration through the nose. Gteneral tonic treatment is always necessaiy. Internally iron, quinine, and strychnine are the best reme- dies. Abscesses sometimes occur in the throat either in the region of the tonsils (see Quinsy) or at the base of the tongue. An acute and alarming inflammation of the loose tissues about the larj-nx is found in connection with abscess, acute larjTigitis, the injecting of scalding fluids or irritant poisons, and as a complication of certain diseases such as smallpox, scarlatina, or Bright's disease. In this condition, known as oedema of the glottis, the swollen and dropsical tissues fill up or overlap the opening of the glottis, preventing the ingress of air and threat- ening immediate suffocation. If not speedily relieved,- o?dema of the glottis causes death by asphyxiation. This afl"ection is treated by punc- ture or scarification of the dropsical sac, the application of leeches over the sides of the larynx, and the administration of pilocarpine. Sometimes intubation, laryngotomy. or trache- otomy may be necessary. Intubation consists in the introduction of a metal or hard-rubber tube between the vocal cords, with a flange resting above them to prevent slipping into the trachea. Laryngotomy or tracheotomy is employed wlien
