106 NAT. ORDER. ROSACELE. 



obtaining a fine blow of roses in the deptli of winter by the most 

 expensive artifices ; and yet fine flowers may be produced early in 

 the spring by any ordinary store, put in operation in December. 

 When the plants are first introduced, keep the air of the house 

 about 55°, never letting it fluctuate to more than two or three degrees 

 below the above. In the second week aim at 60' as the standard , 

 m the third week 65°. When a month has nearly elapsed, begin to 

 increase the heat gradually to 70° : having brought it to this stand- 

 ard, let it afterwards exceed it from three to five degrees, rather than 

 sink below. A succession may be kept up by introducing some pots 

 every eight or ten days. 



Insects. All the species of Rosa are very liable to the attacks of 

 insects, especially of the aphides : some, particularly the Briar and 

 Scotch Rose, are attacked by the cynips rosa; which, by puncturing 

 the bark, occasions the production of rose-galls, and of those massy 

 tufts often seen on wild roses, which were formerly known under the 

 name of bedequar, and used in medicine. A great number of insects 

 seem fond of the flowers of roses, from the earwig to the seemingly 

 harmless lady-bird, which deposits its larvae in the leaves of various 

 species, both wild and cultivated. There seems no remedy for in- 

 sects on plants in the open air so simple and effectual as gathering 

 them by hand, or removing the leaf on that part of the shoot which 

 is infected by them. Under cover, tobacco smoke will prove an ef- 

 fectual remedy for the aphides ; but the larvae of many others, and 

 especially of the tipula and the tenthredinidae, which occasion the 

 wrapping up and shrivelling of the leaves, can only be removed by 

 hand. 



Medical Pmperties and Uses. See Jiosa centifolia, Vol. I., p. 6 ; 

 or Rosa Canina, p. 88 of this volume. 



