Arhoricultural Notices. 269 



their plants, which would suffer little from cold, provided air were made to 

 circulate freely among them, and damp were guarded against. The beautiful 

 tribes of ^rica and E'pacris will suifer little or nothing in a cold greenhouse, 

 although the thermometer in the open air may indicate several degrees 

 below freezing ; while the sudden application of fire heat will probably kill 

 them. 



Mr. M'Nab mentioned that the superiority of the span-roofed form was 

 strikingly exemphfied in the Society's garden about the middle of February 

 last (IS-tS), when the self-marking thermometer in the open air, during dif- 

 ferent nights, indicated 20", 15°, and even 10° Fahr. During these frosts no 

 heat whatever was applied to the span-roofed house, which contained a 

 general collection of soft and hard wooded greenhouse plants. On the 

 mornings of the 17th and 19th of February, the mercury in tlie thermometer 

 within the house stood at 25°, or seven degrees below freezing; yet only two 

 or three plants which were standing near the upright glass of the south end 

 of the house, and were thus exposed to the mid-day sun, suffered from the 

 intense cold to which they had been subjected. The temperature in the 

 span-roofed house always remained much more equable than in the lean-to 

 house. This was signally remarkable at 1 p. m. of the 14th of February, when 

 the thermometer in the open air indicated 56° ; in the lean-to house 70° ; and 

 in the span-roofed house 43° : in the lean-to house, therefore, where the 

 whole glass roof was fully exposed to the sun's meridian rays, the temperature 

 thus becoming fourteen degrees higher than the open air, and twenty-seven 

 degrees higher than in the span-roofed house. 



Having enlarged on the advantages of this form of greenhouse during 

 winter, we shall only briefly state, in conclusion, that, in the warm weather of 

 summer, the span-roofed house admits the freest possible circulation of air, 

 by means of upright sliding sashes on both sides of the house ; while the 

 rafters and astragals of the glazed roof break and intercept the sun's rays, 

 and help to shade the plants from their direct influence ; and that in such a 

 house the plants, instead of being drawn up and weakly, continue firm and 

 bushy ; that they remain much longer in flower ; and that the colours of the 

 flowers are generally brighter. {Edinburgh Advertiser, April 11. 1843.) 



Art. XI. Arboricultural Notices. 



Famous nntdrctica, Arb. Brit. p. 1982., and E. of Trees and Shrubs, figs. 1702. 

 and 1703. p. 910., has been introduced from Tierra del Fuego, by Dr. Joseph 

 Hooker, and there are plants at Kew, and in Mr. Knight's Exotic Nursery. 



Ribes BeatmiW, a hybrid raised by Mr. Beaton, between R. sanguineum 

 and R. aureum, is now beautifully in flower in Lee's Nursery. It is a vigor- 

 ous-growing plant, with long racemes of flowers, partaking of the colour of 

 both species. 



Magmlin Alexandrina, a hybrid between TNI. consplcua and M. purpurea, 

 or perhaps M. p. gracilis, one of the most desirable of deciduous magnolias, 

 was in full flower in Lee's Nurser}' on April 1st, when not a single flower 

 bud of M. Soulange«H« was expanded, and when M. consplcua was just 

 going out of bloom. Thus, by having plants of these three kinds, a succes- 

 sion of bloom will be kept up from the first week in March to the first week 

 in May. 



Art. XII. On a Modeof groioing late Melons. By B. 



Agreeably to promise I now attempt to send you an account of my method 

 of growing late melons, which, as I have practised it with complete success 

 3d Ser.— 1843. V. t 



