HYLODES. 395 HYMENOPTEEA. HYLO'DES. A genus of cystignatliine frogs, about oU species of which are known in tropical America, all small and like tree-frogs, with the I fingers free and provided with undivided disks. A typical and familiar species of the West Indies {Hijlodcs M'lrtiiiiccnsis) has some remarkable traits, described under CoQUl. HY'LOPHYTES (from Gk. liAr/, hyle, forest, matter + (pvrdi', jihyton, plant). Plants which grow in the woods; forest plants. The hylo- phytes are contrasted with the poijphytes, i.e. the plants of grasslands. HY'LOZO'ISM (from Gk. iilri, hyle, matter, wood + Cv'ii', ^ooji, animal). Tlie assumption that the principle of all change is to be found in material substance, and that all matter is in- stinct with life. The term is applied to the Ionic School (see Greek Philosophy), which sought the explanation of the universe in terms of water, air, fire, etc., and thus assumed, with- out further investigation, that matter in one form or another had in it 'the promise and po- tency' of all change, including vital processes. HYMANS, e'miiN', Louis (1829-84). A Bel- gian liistorian, poet, and publicist, born at Rot- terdam. He was editor of various papers, and director of the Echo du Parlcment, a liberal journal. He was elected a member of the Belgian Chamber of Representatives for the city of Brus- sels (1859), held that post for eleven years, and showed himself an upright and conscientious politician. He was the author of several novels, of LettrcH moscovites (1857) ; Ilistoire popiilaire de la Belgiqne (18th ed. 1880); Histoire popu- In ire du rigne de Leopold I. (1864); Histoire politique et parlementaire de la Belgique (1869- 70); Notes et souiKnirs (1876); Types et silhouettes (1877), reminiscences; and Brux- ellcs a travcrs les ages (1883-89). — His brother, Henrt Simon (18.36 — ), an author and critic, was born at Antwerp. He was appointed con- servator of the Royal Library of Brussels, and became a constant contributor to art journals. His best-known w'ork is Histoire de la gravurc dans Vi-colc do Ruhcns (1879). HY'MEN, or HY'MEN.ffi'TJS (Lat., from Gk. 'T/iz/x). The Greek god- of marriage, whose name survived in the refrain of the marriage song, though the original meaning ('begetter') was forgotten, and many legends devised to ex- plain the occurrence in the hjTun. The mvths usually represent him as son of Apollo and a Jluse, more rarely of Dionysus and Aphrodite. In art he is usually represented as a youth of delicate, almost feminine beauty, with a crown of (lowers and a torch ; more rarely with wings. Consult; Schmidt, De Hymenwo et Talasin (Kiel, 18S6) ; Vsoner..a(Jtlername>i (Bonn, 1896). HY'MENOCEPH'ALtrS (Neo-Lat., from Gk. Vfi>!i hynifn, mcmliranc + Kt<t>n7.!i, Iccphalc, head). A genus of small pelagic fishes of the tropics, of the family IMacruridie (see Gren.v mER), noted for the papery nature of the bones of the cranium. The only known species (Hy- mnwcepliiihis cai'miirus) is gray, with silvery tints on the sides, and was taken from deep water in the Gulf of Mexico. See Plate of CoDnsii AND AlMES. HYMENOPHYLLITES. h{-m6n'6-fiHl'tez, Axn HYMENOPHYLTLUMtXeo-Lat. nom.pl., from Gk. v/^'/v, hymen, membrane -|- ipO?.}.ov, Vol. X.— 26. phyllon, leaf). A genus of ferns, comprising the film ferns and lace ferns, found growing parasit- ically on roots of trees and in other like situa- tions, and characterized by their delicate mem- branaceous leaves with cup-shaped spore-cases situated at the ends of the veins, and their creep- ing rootstocks. The family containing them is one of the most primitive of the modern ferns, and also one of the earliest to appear in the geological records ; for fossil leaves, called Ily- nienophyllites, very similar to those of the mod- ern living genus Ifymenophyllum, are found in the Devonian rocks of Euroi)e. It is also known in the coal-measure flora of Carboniferous time, and in the Eocene flora. The fossil fern genus Sphenopteris is very similar in form to Ilymeno- pbyllites, and can with dilliculty be distinguished from the latter. See Fern. HY'MENOP'TERA (Lat. nom. pi., from Gk. iifievdiTTcpoc, hynienopteros, membrane-winged, from i/J>iv, hymen, membrane -- Trrcpoi', pteron, wing). An order of insects, containing the ants, bees, wasps, ichneumou-fiies, saw-flies, gall-tlies, ' and related insects, elsewhere described under their names. The order includes a very great number of species, estimated at about one-fourth of the whole class, of which some, as anls and bees, are singularly interesting and impor- tant. They have the mouth furnished with man- dibles for cutting and tearing, but the other parts of the mouth are adapted for suction, and are generally narrow and elongated, often united into a kind of proboscis, as in bees. (See Bee.) The antennre are generally slender, but often exhibit diflerences in the sexes of the same spe- cies. The wings are four in number, the first pair larger than the second, the wings of the same side united in flight by little hooks. The wings, when at rest, are laid over one another horizontallj' over the body. The witigs are en- tirely membranous, not reticulated as in the Xeuroptera, but with comparatively few ner- vures, the arrangement of which is so constant in the whole order that ]>artieular names have been given to them and to the space between them, and their diversities have been made use of in classification. The wings arc wanting in the imperfectly developed females ("neuters") of some. Besides the ordinary eyes, all the Hy- menoptera have three small, simple eyes (ocelli), on the top of the head. The abdomen is generally united to the thorax by a slender pedicel. The abdomen of the females is generally furnished with an organ capable of being protruded, but for different purposes in difl'erent sections of the order, it being in some of the groups an ovi- iwsitor or borer, and in others a sting. The Ilymenoptera in their perfect state gener- ally feed on honey, but some of them prey on other insects, which are the food of the larva of a greater number; while the larva- of some feed on various vegetable substances. The meta- morphoses of the insects of tliis order are per- fect: the larvie are generally — although not in all the families — destitute of feet: the pupa> take no food. The H^Tiienoptera are remarkable for the dilatation of the tracheie or air-tubes into vesicles, and the general perfection of the respi- ratory system. The instincts and even apparent intelligence displayed by some of them — particu- larly the social kinds, which live in communities — have excited admiration from the earliest times. See Insect, paragraph f<orinl Insects.
