148 
NOTICE ON THE CULTURE OP THE POLYANTHUS. 
ciple. The openings communicating with the ventilators in 
the hack wall, are 2 feet 9 inches long, by 1 foot in height. 
Fig. 3 is a transverse section of the house, in which are 
shown the tanks, pipes, pathway, pits, and the vacuity for 
ventilation, in the back wall. 
The front wall is 3 feet high to the top of the plating ; and 
the angle of the rafters is 32° to the plating. 
The platings are 6 by 3 inches bevelled ; the rafters 51 by 
3 inches ; and the bars inches deep, — the whole filled in 
with sheet glass. 
The manner of constructing the ventilators in the back 
wall is as follows: — In each bay of the roof there is a ven- 
tilator, raking at the top parallel to the pediments, and 
about 2 feet 9 inches width, and 3 feet in height. These 
ventilators, or openings, inside communicate with the 
vacuity in the back wall, (shown in the section,) and the air 
passes out through the openings shown in the front elevation. 
The ventilators or shutters inside are made to slide up and i 
down in a wooden frame fixed to the wall, and are balanced | 
by a line, pulley, and leaden weight, so that they will rest 
at any point required. Where neatness is desired, the ven- 
tilators may be trellised with fillets of wood ; and a wooden 
trellis is fixed to the back wall, to which the stems of the 
plants are trained. 
The house is heated on the tank system, by one of Bur- 
bidge and Healey’s ribbed boilers, and 4-inch flange pipes. f 
It will be seen by the section, that the tank at the back part 
of the house is on a higher level than that in front ; this is 
in order that the flow pipes from the top of the boiler may 
descend from the back tank, pass under the pathway, and 
proceed along the front tank as a return pipe to the boiler. 
The four pipes shown in front are the flow and return pipes, 
from and to the boiler. 
Fig. 4 is a section of the tank, &c.,on a scale of one- third 
of an inch to a foot. The water in the tank generally covers 
the pipe about an inch over its surface, leaving a small space 
between the surface and the tank cover. 
NOTICE ON THE CULTURE OF THE POLYANTHUS. 
The Polyanthus — Primula elatior Polyantha .• — These plants are natives of Britain ; the 
time when they were first brought under the florist’s notice as objects worthy of culture, 
cannot be traced with any degree of certainty. The mode of culture is the same as that 
recommended for the Auricula. It may be as well, perhaps, to suggest the properties 
requisite to form a perfect specimen of this class. They consist in, — 1st, A compact and 
well-grown plant ; 2nd, Flower-stems 6 inches in height, round, erect, and sufficiently 
strong to support the truss of bloom ; 3rd, truss large, round, and compact, consisting of 
seven or more pips ; 4th, Foot-stalks of the flowers strong, elastic, and equally divided ; 5th, 
The pips should measure 1 inch in diameter, be quite circular, smooth on the edges, and 
perfectly flat ; 6th, Tube one-sixth the diameter of the pip, same colour as the eye, well- 
filled with anthers in a perfect state; 7th, The trumpet or edging round the tube, must 
be circular, and rise a little above the eye ; 8th, Eye of a yellow or lemon colour, quite 
circular, measuring half-an-inch in diameter including the tube ; 9th, Ground colour should 
be solid, dense and rich, and of the same width as the yellow T round the tube, forming a 
band on the inner side (the outer should be clean on the edge) ; 10th, The lacing round 
the edge of the pip must be well-defined and smooth; 11th, The bar which divides the 
segments of corolla, should be whole, of even width, joining the lacing to the yellow eye ; 
12th, The yellow must be distinct, marking the same. 
The following are a few good varieties for exhibition : — Collier’s Princess Royal ; 
Pearson’s iVlexander; Huffton’s Lord Rancliffe and Squire Ray; Bullock’s Lancet; 
Bernard’s Formosa ; Buck’s George the Fourth ; Crawshaw’s Invincible ; Nicholson’s 
Bang Europe; Coxe’s Prince Regent; Fletcher’s Defiance; and Clegg’s Lord John 
Russell. The same remarks apply equally to this class of flowers, as to the foregoing. 
INSECTS INFESTING THE GENUS PRIMULA, 
INCLUDING THE VARIOUS KINDS OF AURICULA, POLYANTHUS, AND PRIMROSE. 
All the various species and varieties of Primula are subject to the attacks of slugs, 
earwigs, and caterpillars of various species of moths, which may be described as follows : — - 
Bride’s-maid Moth ( Triphana Pronuba ). — The wings of this moth are two inches 
and a quarter in expansion. First pair grey, deeply clouded with reddish-brown. Second 
pair yellow orange, with a broad black band near the yellow margin. This in most 
seasons is a very common insect. The caterpillar is a dull brownish green, marked 
with two rows of black spots down the back. The parent lays her eggs about the 
beginning of August, and the caterpillars commence their ravages just above the surface 
of the soil, feeding only in the night, and retiring beneath the earth in the day. In 
winter they become partially torpid, and may be found coiled up beneath the shelter of 
s 
