88 
FLORICULTURAL NOTICES. 
outside of the frame, to the palpable obviation of its dangerous diffusion through 
the atmosphere. The primal expense of this system may be made an objection, 
but the undecaying nature of the material, and its ready appropriation to more 
permanent purposes, will meet that complaint ; while the advantages it would 
confer must be at once apparent. 
For the exclusion of frost, we have a somewhat novel method to propose. 
Some of our readers may, perchance, have met with it in the establishment to 
which we are indebted for the hint, and where it has been practised for several 
years ; but to most of them we imagine it will be new. It consists in the forma- 
tion of slender frames, of deal or other slight wood, of the precise size of the light 
they are intended to cover, with two diagonal bars of a yet weaker nature, crossing 
each other in the centre, and fixed at the four corners. Over these, a sheet of 
very strong and close canvas is stretched, and fastened to the frame all round, as 
well as to the transverse bars. The whole is then thickly covered with pitch, of 
which two coatings may be applied, if it is thought desirable. 
The superior adaptation of such a covering to the purposes of shelter cannot be 
doubted. By thoroughly coating it with pitch, all the interstices of the canvas 
are filled up, and it acquires a degree of impermeability which no other light 
substance can possess, and which is eminently useful in the retention of heat. The 
frames may be kept during the summer in any dry shed, and if a little fresh pitch 
be added as soon as indications of its need are observed in the canvas, they will 
last many years, and be extremely serviceable. We regard the scheme as most 
excellent, both for its efficacy and economy, and sincerely desire its universal 
adoption. 
Our final hints on Pelargonia will be given in the next Number. 
FLORICULTURAL NOTICES. 
NEW AND RARE PLANTS FIGURED IN THE LEADING BOTANICAL PERIODICALS FOR 
APRIL. 
Brassia Lance ana ; var. viridiflora. In the general colour of its flowers 
this plant has a great resemblance to the old B. maculata, but their size, peculiar 
markings, and narrow exterior parts, properly associate it with B. Lanceana, from 
which, again, it is only separated by its light green blossoms, and somewhat more 
attenuated sepals, which are indistinctly tinted with yellow, but far from being so 
much so as those of that species. C. S. Parker, Esq. imported this variety from 
Demerara, and it produced its interesting blooms in the collection of this gentleman 
at Annesley, near Liverpool, in September 1839. Its principal recommendation, 
besides the lively green and pleasing spotting of the blossoms, is their delicious 
odour. Bot. Mag. 3794. 
