AND GENERAL HORTICULTURE. 



375 



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be fixed in the centre and at exact right 

 angles. Before using them it is necessary 

 that two points should be fixed, preferably 

 at the extreme ends of the ground to be 

 leveled. If level pegs are inserted at these 

 points, and two of the three rods allowed 

 to rest on them, as many intermediate pegs 

 may be inserted as are thought necessary. 

 This is done by a third person with the other 

 rod, who drives the pegs in as he is directed 

 from one of the ends. The tops of the pegs, 

 if the leveling is properly done, should then 

 show all the inequalities in the soil for the 

 guidance of the workmen. As the light is 

 found most deceiving at a distance, one of the 

 rods is sometimes made an inch longer than 

 the others, and a small hole pierced through 

 the cross-piece, by using which many may be 

 able to work more correctly than if all the 

 rods were of equal length. 



Roe'lla. African Hare-bell. In honor of Wil- 

 liam Roell, Professor of Anatomy at Amster- 

 dam. Nat. Ord. Campanulacece. 



A genus of greenhouse shrubs or spreading 

 herbs, natives of South Africa ; they have 

 generally blue -flowers, which have somewhat 

 of the dazzling glossy hue of Venus's Looking 

 Glass. The shrubby kinds are of low growth, 

 and rather difficult to propagate ; but the- 

 annual species are of very easy culture, and 

 only require the usual treatment of half- 

 hardy annuals. 



Roeme'ria. Purple Horned-Poppy. In honor 

 of John James Rcemer, professor of botany at 

 Landshut, and author of several botanical 

 works. Nat. Ord. Papaveracece. 



R. hybrida, the violet-flowered Horned- 

 Poppy or Wind Rose, the best known species, 

 is a very beautiful purple, annual flower; but, 

 unfortunately, its beauty is so very short-lived 

 that it is difficult to find a perfect flower, as 

 one or two of its petals drop almost as soon 

 as the flower expands. It is quite hardy, and 

 only requires to have its seeds sown in the 

 open border in April. 



Roe'zlia. Named in honor of Roezl, a well- 

 known collector who travelled in Central 

 America, Mexico, etc. Nat. Ord. Melastom- 

 ace<s. 



R. Granadensis, the only species yet intro- 

 duced, is an erect plant-stove shrub, with 

 carmine-purple flowers, and opposite, ovate- 

 lanceolate, hairy leaves. It was introduced in 

 1872, and is easily increased by cuttings. 



Roffia. See Raphia. 



Rogie'ra. In honor of M. Charles Rogier, a Bel- 

 gian statesman. Nat. Ord. Rubiacece. 



A small genus of evergreen shrubs from 

 Central America, allied to Rondeletia. In 

 general appearance they resemble the Laurus- 

 tinus. They are very pretty green-house 

 plants with bright pink flowers, and are 

 easily increased by cuttings. 



Ro'hdea. In honor of M. Rohde. Nat. Ord. 

 LiliacecB. 



R. Japonica is the only known species of 

 this genus. It is a green-house, herbaceous, 

 nearly aquatic plant, and a very interesting 

 one for the green-house, having dark-green 

 foliage and spikes of creamy white flowers, 

 which are succeeded by spikes of showy fruit. 

 There are three variegated varieties of this 

 plant, all of which are most showy green-house 



ROM 



plants, and are well worthy of cultivation. 

 Syn. Orontium Japonicum. 



Rollers and Rolling. The importance of, and 

 the benefit derived from, using a roller on the 

 lawn, especially in spring, is not fully appreci- 

 ated. Freezing and thawing during winter 

 causes the ground to heave and become un- 

 even, and if it is not pressed back firmly with 

 a roller, before hot weather, the grass is apt 

 to be injured, or even killed in spots, besides 

 leaving the surface very uneven for the 

 mower. They are also useful for pulverizing 

 the soil in the garden if it gets very dry and 

 hard, as well as for firming in seeds such as 

 Onions, Turnips, etc., that are generally 

 sown in large breadths, and where they can 

 be used to advantage. They are also requisite 

 in every well-kept garden for keeping the 

 walks firm and in good condition. They are, 

 moreover, indispensable on the farm, both for 

 firming the pasture in early spring, and com- 

 pacting the earth round newly sown seeds, 

 etc. We quote from our work, "How the 

 Farm Pays," page 46. " While you, as a 

 gardener, advocate the use of the feet to 

 firm the soil, in sowing and planting, I, 

 as a farmer, advocate the use of the roller. 

 The object in both is the same ; and I am 

 satisfied beyond any shadow of a doubt, 

 that millions and millions of dollars are 

 annually lost to the farming community, 

 through a want of the knowledge of the vast 

 importance of firming the soil over the seed. 

 This is particularly the case with Buckwheat, 

 Turnips and other crops that are sown from 

 the month of July until September, as at such 

 seasons we very often have long-continued 

 droughts, and the soil is like a hot ash-heap, 

 and to expect germination from small seeds 

 when sown in such soils, without being firmed 

 against the entrance of the hot air, is just 

 about as useless as if we threw them in the 

 fire." 



Roman Hyacinth. See Hyacinth. 



Romanzo'ffia. Named in honor of Count Rom- 

 anzov, a Russian nobleman, who was a patron 

 of scientific studies. Nat. Ord. Hydrophyl- 

 lacece. 



A genus of only two species of dwarf her- 

 baceous perennials, having much the appear- 

 ance of Saxifrages, natives of the sub-arctic 

 regions of eastern Asia and western America. 

 jR. Sitche,nsis, the Sitka Water Leaf, the only 

 species yet introduced, is a dwarf plant with 

 reniform leaves, and white flowers ; it is an 

 excellent plant for the rock-garden. 



Rome'ria. A synonym of Rozmeria, which see. 



Ro'mneya. The Californian Tree Poppy. 

 Named after The Rev. T. Romney Robinson, 

 an astronomer, of Armagh. Nat. Ord. Pap- 

 averacece. 



R. Coulteri, the only species, is a very 

 showy, tall, glabrous, herbaceous perennial, 

 with large white flowers terminating the 

 branches. It is increased by seeds in spring, 

 and requires protection in winter. A native 

 of California, introduced to cultivation in 

 1875. 



Romule'a. Commemorative of Romulus, the 

 founder of Rome. Nat. Ord. Iridacece. 



A genus of very pretty hardy or green-house 

 bulbs, removed from Trichonema. They are 

 natives of western Europe, the Mediterranean 



