I ', nous indusia ; and being usually opposite, 



j the iudusia in the early stages of growth 



nearly meet across the back of the little 



| [ segments iuto which the frond is divided. 



It belongs to the free-veined Pteridece, and 



j contains but three or four species, found 



chiefly in subtropical and temperate India 



i and Japan. One, however, is Abyssinian, 



; and one West Indian. [T. MJ 



I ONTGBWA. A curious genus of asco- 

 ] myeetous Fungi growing for the most part 

 ; on auiiual substances, as hoofs, horns, fea- 

 : tbers, wool, bones, &c, one of which is 

 . intimated bythe generic name. They look 

 like minute mostly stipitate puffballs, but 

 they differ materially in their fruit. The 

 TulasDes were the first to indicate the true 

 structure in this genus. Whether the 

 species which grow on wood are really 

 closely allied must be determinedby future 

 observation ; at present it would seem that 

 they are more nearly allied to P'dacre than 

 Onygena, unless the latter genus should 

 prove to have species with both sporife- 

 rous and sporidiiferous fruit. Three 

 species at present have occurred in Eng- 

 land, one of which, occurring on bones, is 

 distinguished from all the others by the 

 absence of a stem. No species has at pre- 

 sent occurred out of the northern hemi- 

 sphere. [M. J. B.J 



OOD-BEG. An Indian name for Areca 

 Catechu. 



OOKBT. An Indian name for the Sugar 

 Cane. 



OOLUNDOO. An Indian name for the 

 seed of Phaseolus radiatus. 



OOLTSIS. Monstrous ovular develop- 

 ment in plants. 



OOMUGGI. Tlie Japanese name for 

 Barley. 



OOPHORIDIUM. The larger form of 

 spore-case in Selaginella. 



OORD. An Indian name for a species of 

 Dolichos. 



I OOSPORANGIA. In some of the dark- 



I spored Algce, as Leathesia and Mesogloea, 

 two kinds of zoospores of different sizes 



i are produced in separate organs. The or- 

 gans which produce the larger are by Thu- 

 ret called trichosporangia, and the others 

 oosporaneia. It is not to be imagined 

 that either of these have the power of 



, impregnation, as both are reproductive. 



j In Cutieria there are organs answering to 

 antheridia, which produce active bodies, I 

 which have neither male functions nor do 



; they germinate. They seem, in fact, to i 

 form a transition between spermatozoids 



j and minute zoospores. [31. J. B.] | 



I OOTRUM. The Indian name for the 

 Store of Dcemia extensa. 



OOWA. A species of Barley grown on 

 the banks of the Sutlej. 



OFAQUE. The reverse of shining ; dull. : 

 Not the reverse of transparent. 



OPEGRAPHA. A genus of lichens be- 

 longing to the order Graphidei, distin- 

 guished by a linear or elliptic simple or 

 forked disk, surrounded by a distinct peri- 

 thecium. Taken in its wider sense, it in- 

 cludes the great mass of those lichens 

 found growing on trees or on rocks, re- 

 sembling Eysterium in their fruit. They 

 are known at once by the strong resem- 

 blance they bear to the characters of some 

 Oriental languages. These lichens are of 

 little practical importance, except in so far 

 as, in company with some other cortical 

 species, they help to enable persons to 

 distinguish different kinds of medicinal 

 bark. ' [M. J. B.j 



OPERA-GIRLS. Mantisia sanatoria. 



OPERCULUM (adj. OPERCULATE). 

 The lid of anything, as in the pitcher of 

 Nepenthes or the fruit of Lecythis; more 

 especially the lid of the spore-case of urn- 

 mosses. 



OPHELIA. A genus of Indian herbs of 

 the gentian family, distinguished from 

 Agathotes by the glandular pits at the base 

 of the segments of the corolla being un- 

 provided with any scale, and by the sta- 

 mens, which are slightly dilated at the 

 base and even adherent one to the other. 

 O. elegans is described as a very elegant 

 species, with light-blue flowers streaked 

 with veins of a darker hue. The stems are 

 used as a bitter tonic, like those of its ally, 

 the Chiretta : see Agathotes. [M. T. M.] 



I OPHIOCARYON. The only species of 

 I this remarkable genus is O.paradoxum, a 

 I large tree peculiar to British Guiana, and 

 i chiefly found on the banks of the River 

 Essequibo and its tributaries. The generic 

 name signifies Snake-nut, and alludes to 

 the curious form of the embryo of the 

 seed, which is spirally twisted so as to | 

 closely resemble a eoiled-up snake, the I 

 radicle or rudimentary root being long and | 

 gradually thickening towards its lower I 

 extremity, and the cotyledons thin and i 

 leafy. The tree has pinnate leaves, and i 

 panicles of minute flowers, producing j 

 roundish fruits rather larger than walnuts. 

 Some of the flowers are perfect and others 

 of one sex only; they have Ave sepals, five 

 petals, ten stamens, two of them fertile and 

 opposite the inner petals, and a two-celled 

 ovary. The fruits are often sent to this 

 country as curiosities, under the name of 

 Snake-nuts or Snake-seeds. They are not 

 known to possess any medicinal properties, 

 but the singular snake-like form of the 

 embryo has induced the Indians to employ 

 them as an antidote to the poison of veno- 

 mous snakes. The genus belongs to the 

 order Sapiiidacece. [A. S.] 



OPHIODERMA. A name sometimes 

 given to the Ophioglossum pendulum, which 

 differs from typical Ophioglossum in having 

 the sterile branches fasciseform and dicho- 

 tomously forked. [T. M.] 



OPHIOGLOSSACEiE. A natural order 

 of ferns, separated from the Polypodiacece 

 by wanting the elastic ring which girts i 



