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OUOBANCHACEjE. (Broomrapes.) A 

 natural order of corollifloral dicotyledons 

 belonging to Lindley's gentianal alliance 

 of perigynous Exogens. They are herba- 

 ceous parasitical plants, having scales in 

 place of leaves; and their didynamous 

 flowers have a persistent inferior calyx, 

 a monopetalous irregular usually bilabi- 

 ate persistent corolla, four stamens, a 

 fleshy disk, and a free one-celled ovary 

 of two carpels, with two or more parietal 

 placentas, the style manifest, with a two- 

 lobed stigma. Fruit capsular, enclosed 

 within the withered corolla, two-valved; 

 seeds indefinite, minute. They are natives 

 of Europe, more especially the southern 

 parts, and of Asia, North America, and the 

 Cape of Good Hope. Their general proper- 

 ties are astringency and bitterness ; and 

 some have been used as tonics, and as ap- 

 plications to indolent ulcers. They attach 

 themselves to the roots of various plants, 

 and are hence called root-parasites. The 

 order contains about a dozen genera and 

 upwards of a hundred species, of which 

 those of Orobanche and Lathrcea are the 

 most familiar. [J. H. B.] 



OROBANCHE. A genus of singular-look- 

 ing parasitic plants typical of the Oroban- 

 chacece, and represented in England by a 

 variety of species which grow severally on 

 the roots of furze, clover, flax, ivy, wild 

 carrot, &c. All the species agree in having a 

 dingy brownish-yellow stem, which is leaf- 

 less throughout but furnished with nume- 

 rous pointed scales, which take the' place of 

 leaves. The upper portion of the stem 

 bears a spike of rather large flowers, of 

 which the calyx is of the same russet hue 

 as the stem ; the corolla is two-lipped, of a 

 yellowish colour tinged with pink or pur- 

 ple-blue and veined ; there are four sta- 

 mens in pairs of unequal length; and the 

 capsule is one-celled, two-valved, many- 

 seeded. 



0. major, the largest British species, is 

 parasitical on the roots of furze and other 

 leguminous plants, and grows to the height 

 of two feet or more. The others attain 

 usually a height of from six to eighteen 

 inches, varying little in habit and general 

 characters, yet so far differing in minute 

 points that botanists reckon up to ten or a 

 dazen species. It may be a question, how- 

 ever, whether the dissimilarity ought not 

 to be referred to the variety in the struc- 

 ture and habit of the plants on which they 

 are parasitic, so that the number of distinct 

 species may be much less than is commonly 

 supposed. [C. A. J.] 



That O. minor, called the Lesser Broom- 

 rape, which we have occasionally observed 

 nearly two feet high, may, after all, include 

 some two or three other forms, is an opi- 

 nion deriving some weight from Dr. Ar- 

 nott's remark, that in all parasitical plants 

 the appearance may be so altered by the 

 structure of the tribe they prey upon, that 

 many reputed species are probably differ- 

 ent states of the same. Thus 0. minor 

 occurs on different clovers, whilst a great 

 number of plants are affected by so-called 



different species. It remains, however, to 

 be determined what amount of difference 

 may be brought about by the same seed 

 electing to grow on different plants. The 

 annexed woodcut shows the mode of at- 

 tachment of the parasite to its foster-pa- 

 rent; and as this is yearly becoming a more 

 formidable enemy to our crops, we recom- 

 mend its further study to the farmer. 



As regards the manner in which this 

 parasitism takes place, we are as yet in the 

 dark. It may be mentioned that perhaps 

 few plants produce more seeds than the 



Orobanche minor. 

 A, the parasite attached to B, an old plant of 

 Alsike Clover ; a, a, section showing the 

 mode of attachment. 



Broomrapes, but they are very minute. It 

 seems certain that seeding affected crops 

 only ensures the spread of the plants where 

 this seed is sown, so that farmers should 

 if possible avoid seed grown where the 

 Broomrape prevails. [J. B.] 



OROBE. (Fr.) Orobus tiiberosus, now 

 called Lathyrus macrorrhizus. 



OROBUS. A genus of papilionaceous 

 Leguminosce, now generally united Avith 

 Lathyrus, from which it cannot be distin- 

 guished by any marked character. There 

 are a considerable number of species, 

 chiefly found in mountainous or woody 

 districts, and dispersed over Europe and 

 Northern Asia. 



ORONCE. (Fr.) Orontium. 



ORONGE. The French name of Agaricus 

 ccesareus, which is at the same time one of 

 the best and handsomest of Fungi. The 

 scarlet pileus, yellow gills, and white 

 volva must make it at all times easy of 

 recognition, and it is to be hoped that it 

 will some day reward our researches in the 

 south of England or Ireland. A form of 

 it was found in the Sikkim Himalayas by 

 Dr. Hooker. This is the species which was 

 so celebrated among the Romans under 

 the name of Boletus, and it was a favourite 

 vehicle for poison in both imperial and 

 papal Rome. It was with this fungus 

 that Agrippina poisoned her husband Clau- 

 dius, to which Juvenal and Martial allude. 

 Martial, moreover, speaks of it some fif- 

 teen times, and places it as an object of 

 luxury above the truffle. [M. J. B.J 



