HYBBIDITY. 362 HYDE. 1897 (Washington, 1898) ; DeVries, Die Muta- tionsthcorie (Leipzig, lUOl): Suclietet, Dcs hy- brides a I'etal snuvayc ( Furis, 1897); Mi'iidcl, Verauche iiber I'flanzvn U ijbridcn. crh. des Aa- tiirfnrxi'hrr Trreinx (Brunswick, ISfifi). HinLiociKAi'iiY (Animals). }>. Standfuss, Unndbiich dcr palnnrkli/tchcn Oronn-f'rhmcfler- lin<ip fiir Forsrhrr und Snnimlrr (.Tenn. 1S96) ; ETperimcntrllr zooloffisrhr Sliidirn mil Lepidop- teren (Zurich, 18'.)8), abstract of results in Pro- ceedings of the Entomological Society of London, pp. 2-5.3 (London, 1897). and in F, A. Dixey, "Recent K.]KTinient3 in Hybridization" {Science Progress, vol. vii., London, 189S) ; .J. C. Ewart, The Pcnyciiik Experiments (London, 1899) ; A. Suchctet, Des hybridcs a Vi'lat stiuiage, torn, i., Classe des Oiseaux (Paris and Berlin, 1897). HYBRIDIZING. See Pl. t-Breedinq. HYDAS'PES. The ancient name of the river Jlielani. in Nurlhwcslern India. Sec Jiielam. HYDATHODE, hl'dath-Od (from Gk. Mup, hydOr, water + orfof, hodos, way). In botany an organ that exudes water. Usually hydathodea occur at the tips of the main veins or branch veins of leaves, and commonly ap|)ear to the unaided eye as leaf-teeth. At the apex of the orjran is a pore which has been variously called water-pore and waterstoma. These pores diflfer from ordinary stomata in the absence of turjior movements, often in size and in their function; they are pas- sageways for liquid water rather than for water vapor, llydathodcs commonly occur in connec- tion with the vascular system, and may be re- garded as a sort of safety apparatus to prevent injection of the air-space with water at times when root-pressure is high and transpiration low. (1) Loneltniilnal oeotion throuKh leat-todli .if I'liinese priiriros** ( y'r/z/Hj/.-i .S'/npojJW ), sbowinK the diverff»'iit trn- cbeitlH. t'Tiiiiiiutiii^r the vascular bundle, the luube epi- theni, and thetPrmtnal pore. ( 2 ) Surface view of a water-stoma (terminal pore of a leaJ-tooth). HYTJATID (Gk. iSari^, hydatis, water- vesicle, hydatid, from Wu/j, hydor' water; con- nected with OChurch Slav, voda, Skt. udnn, water, and ultimately with Goth, irafd, OHG. uazzor, Ger. Wasser, AS. wwter, Eng. water ; AS. tccEt, Eng. wet; OHG. ottar, Ger. Otter, AS. otor, Eng. otter). The bladder-worm. It is allied to the tapeworm, but difTers in being bladder like, and similar in shape to the 'cysticercus' of the tapeworm. The beads bud on special brood- capsules in such a way that their invagination is turned toward the cavity of the veijicle. About uOOO eggs are developed in a single 8«'gnicnt (proglottis). The six-hooked embryos develop, are expelled from the dog, the first host, and find their way in drinking-water or in food into the human intestines, whence they bore into the liver, their favorite habitat, or are carried along the blood-vessels into some other organ, where they develop into bladder-like iKidies or 'hydatids' {Echinococcifcr echinococcus) . By the fourth week the young is '.j nun. ( l-.iO inch) in Icnglli, and it is probably many months before the echi- nococcus heads are entirely develii|H-d. The worms become sexually mature in from seven to nine weeks after this stage is reached, when the milk-white worms may usually be found im- bedded in the mucus of the duodenum and upper part of the small intestines, with their heads attached to the villous surface of the intestine. The parent vehicle may grow as large as a man's iiead. The cyst in which the bladcier-worm lies, and which is caused by it, is called a 'hydatid cyst." There axe two forms of this hydatid, one (Echinococcifcr hominis) living in man, and the other (Echinococcifcr trterinorum) in domestic animals. When these echinococcus cysts remain sterile, a.s they frequently do, they .are called 'accphalocysts.' "Another, and indeed pathologi- cal form," says Sedgvick, "is the so-<alleil iiiul- tilooular' echinococcus, which was for a long time taken for a colloid cancer. It is also found in mammalia (in cattle), and here presents a confusing resemblance to a mass of tubercles. The echinococcus disease (hydatid plague) was wide- ly spread in Icel.and. This disease, likewise, seems endemic in many places in Australia." HYDE. A manufacturing town in Cheshire, England, seven miles ea.st-southea.st of Man- chester (Map: England, D 3). Since the exten- sion of the cotton trade, it has rapidly increased in size. Besides numerous cotton factories, print and iron works, there are considerable manufac- tures of machinery and hat.s. Coal abounds in the neighborhood. The neighboring district is densely peopled, and ha.s abtmdant means of communication, by railway and canal, with all the important towns in the vicinity. Hyde is mentione<l as a village in the reign of King .John; it was incorporated as a municipal borough in 18S1. It owns its water, markets, cemetery, and maintains free baths, library, hospital, and fire brigade. Refuse is consumed by a destructor, and sewage is chemically treated for fertilizing purposes. Population, in 1891, 30.700; in 1901, 32.S00. H-YDE, AXXE (1637-71). The first wife of .Tames II. of England. She wa.s the eldest daugh- ter of the Duke of Clarendon, and was born at Crnnbourne Lodge, the house of her grandfather, Sir Thomas Aylesbury, in Windsor Park. When she was twelve years old she went to Holland with her mother and sisters, and in 16.54 was ap- pointed main of honor to the Princess of Orange, at whose Court she wa.s a great favorite. It was while accompanying the Princess on a visit to Paris in 16,56 that she first met .Tames, then Duke of York. She became engaged to him about a year before his return to England in the spring of 1660. and in spite of the most vehement op- position from all quarters, was privately mar-
