173 



HYPEROODOK. 



HYRAX. 



174 



H. criapum has a round branched stem, sessile lanceolate leaves, 

 sinuately waved at the base, full of dots, small blunt sepals. It is 

 native in the regions of the Mediterranean, and is the "ttrfpiKov of 

 Hippocrates ('Moi-b. Mul.' i. 610) ; also of Dioscorides (iii. 161), and 

 the Hypericon " quod alii chamaepityn, alii corion appellant " of Pliny 

 (xxvi. 8 ; xxvii. 4, 5). At the present day it grows near the sea in 

 Attica. 



H. perfolialum, the ' \vp&a<upv of Dioscorides (iii. 163). It has a 

 2-edged stem ; ovate clasping dotted leaves ; fringed and dotted sepals 

 and petals, and sessile flowers. It is a native of Italy. 



//. Corit has a shrubby erect round stem, linear leaves in whorle, 

 with revolute margins, and a bluntish linear calyx. It is the Kipis 

 of Dioscorides (iii. 174), and the Coris of Pliny (xxvi. 3). This species 

 is a pretty little shrub, native of the Levant, and in dry places in the 

 south of Europe. 



H. organifolium is distinguished by its ascending downy stem, 

 ovate blunt and pubescent leaves full of pellucid dots, numerous 

 stamens, and many black dots in the corolla. It is a native of the 

 East, about Constantinople, Thrace, and Armenia, and is frequently 

 found on high mountains in company with H. perfoliatum. It in pro- 

 bably the 'h-fhpcnov of Dioscorides (iv. 5), and undoubtedly the 

 Ageratum of Pliny (xxvii. 4). 



//. Oly m pic um has elliptical lanceolate leaves full of pellucid dots ; 

 a round stem, and withering corolla and stamens. It is a native of 

 Mount Olympus and of China. Fraas thinks it probable that this is 

 the floKfftMvtov of Dioscorides (iv. 8). 



Most of the sptcies of ffypericum are showy, and deserve cultiva- 

 tion. The hardy herbaceous kinds will thrive in any common garden 

 oil, and are easily propagated by dividing the roots or by seeds. Those 

 that require the greenhouse or frame will thrive best in a mixture of 

 loam and peat, and strike root readily in sand under a bell-glass. 



(Don, bicldiiiiiijilcoui Plants ; Babingtou, Manual Brit. But.; Fraas, 

 Synopsis Plantarum Flora Claaicce.) 



HYPEROODOX. [CETACEA.] 



HYPERSTUEXE. [Acorn:.] 



HYPERSTHENE ROCK. This is among the rarer varieties of 

 those igneous aggregates which by many geologists are grouped 

 together under the title of Trap. Dr. M'Culloch, who first noticed 

 Hypersthene Rocks in Skye and Arduamurchau, describes three 

 varieties : 



Hypersthene with Compact Felspar. 

 Hypersthene with Common Felspar. 

 Hypersthene with Glassy Felspar. 



In largeness of grain it varies from large-grained granite to ordinary 

 greenstone, or is even as fine as basalt; the Felspar is of various 

 colours. It passes to common greenstone. 



In Skye it forms the C'uchullin Mountains ; part of the mountain 

 of Carrock Fell in Cumberland is also formed of it ; a dyke of Hypers- 

 thenic Trap was noticed in Radnorshire; it occurs also in Cornwall. 

 In the Valteline H. Necker has pointed out the passage from Hypers- 

 thcuic Sienite to Granite. 



HVI'H.KN'E. [PALMACE*.] 



HYPNEA, a genus of Plants belonging to the natural order 

 Ceramiaceai, or Rose Tangles. In the Greek Archipelago medicinal 

 qualities as a vermifuge are attributed to //. mugciformis. 



Several species furnish Iodine, which gives them their peculiar 

 odmir. 



HVPNUM. [MuucALES.] 



HYPO'CH(ERIS, a genua of Plants belonging to the natural order 

 Compositor, to the sub-order Cichoracea, and to the section Hypochce- 

 ridece, which has a scaly receptacle and a feathery pappus. The heads 

 are many-flowered, the involucre is oblong and imbricated, the fruit 

 glabrous, muricated, and beaked ; the pappus in two rows, the outer 

 short and setaceous, the inner long and feathery. There are two 

 British species of this genus JI.gla.br a, with oblong dentate-sinuate 

 leaves, and II. radicata, with runcinate obtuse leaves. They are 

 found on dry and gravelly places and waste places. (Babingtou, 

 Manual of Britii/t Botany.) 



HY'POGENE, a term in Geology, implying ' nether-formed' (from 

 farb, below, and ytv, the root of yiyvo^utt, which signifies * birth,' or 

 'formation'), proposed by Sir Charles Lyell as a substitute for the 

 word Primary. He affirms that " the popular nomenclature of geology, 

 in reference ,to the rocks called Primary is not only imperfect, but in 

 a great degree founded on a false theory ; inasmuch as some granites 

 and granitic schists are of origin posterior to many Secondary rocks. 

 In other words, some primary formations can already be shown to be 

 newer than many secondary groups a manifest contradiction in terms." 



As far as Granite is concerned, this remark is entirely true : its 

 origin i proved to be independent of any particular epoch, and it 

 has been long thrown out of the modern catalogue of primary rocks. 

 A* applied to granite, Mr. Lyell's emendation is exactly equivalent 

 to the term Plutonic used in Brongniart's classification ; but when 

 the term Hypogene is used to include the primary stratified rocks, a 

 particular hypothesis of their origin is tacitly assumed, which many 

 geologist* think not sufficiently established. 



It is assumed in this hypothesis that the primary strata have 

 acquired their present mineral aspect, not through any circumstances 

 peculiar to their original formation, and supposed to be characteristic 



of the physical agencies exerted in the earlier eras of the world, but 

 through the subsequent agency of heat and chemical forces in those 

 regions, and under those circumstances where the Plutonic rocks are 

 generated. The term Primary implies only that the rocks so named 

 are the earliest we can trace in the crust of our planet ; and as geo- 

 logical classification is mainly founded on succession of time, and the 

 relative antiquity of strata can be determined as a fact, it seems 

 unlikely that the well-known designations of Primary, Secondary, and 

 Tertiary Strata will be abandoned, though, as expressing the subter- 

 ranean origin of certain properties and conditions of mineral masses, 

 the word Hypogene appears very suitable. 



(Lyell, Principles of Otology.) 



HYPOPITYS. [MONOTROPA.] 



HYPOXIDACE^E, Hypoxids, a natural order of Endogenous 

 Herbaceous Plants, with a tuberous or fibrous perennial root. Leavea 

 always growing from the root and crown, nowhere else, linear entire, 

 plaited, of a dry texture. Scapes simple or branched, occasionally 

 very short. Flowers complete, hermaphrodite. Perianth petaloid, 

 adherent to the ovary, 6-parted, with the sepals coarser than the 

 petals. Stamens 6, inserted into the base of the segments of the 

 perianth ; filaments distinct ; anthers turned inwards, 2-celled, erect, 

 opening lengthwise. The number of the plants of this order is very 

 inconsiderable. Those that are known inhabit the Cape of Good 

 Hope, Australia, the East Indies, the tropics of America, and the 

 warmer parts of the United States. 



The roots of Curcidigo orchioidet are somewhat bitter and aromatic, 

 and are employed medicinally in India. The tubes of C. stans are 

 eaten in the Marianne Islands ; those of Hypo.cis crecta are employed 

 by the aborigines of North America iu healing ulcers and against 

 intermittents. 



(Lindley, Vegetable Kingdom.) 



HYPSIPETES. [LANIAD^.] 



HYPSIPRYMNUS. [KANGAROO.] 



HYPUD^EUS, the more correct mode of writing ffipudceus; but 

 the latter form is generally used by the French zoologists. 



HYRAX, a genus of Mammalia of small size, but of great interest, 

 in consequence of the peculiarity of their organisation, which has led 

 modern zoologists to assign them a place among the Pachydermata, 

 though their external appearance, when cursorily examined, would 

 seem to point out their relationship to the Rodentia, among which 

 they have been erroneously classed. 



2 7 "7 



Dental Formula Incisors, ; canines, ; molars, = 34. 



Teeth of Hyrax. F. Cuvier. 



Cuvier observes that there is no species of Mammalia which proves 

 more completely than IIyra.c the necessity of having recourse to 



