October 5, 1889. 
THE GARDENING WORLD 
73 
vacated. The process of depositing the eggs, and the 
exit of the maggots from the leaves, are so nicely 
performed that I have been unable, even with the 
assistance of a powerful glass, to find out either the 
places of deposit or the doors through which the 
maggots depart. I leave these to be discovered by 
some scientific entomologist, and for his guidance I 
forward herewith several chrysalids of the maggot 
(measuring about 3-32 in. in length) taken from the 
Carnation and Pink in the maggot state ; also half a 
dozen flies which I have hatched from other chrysalids 
of the same kind, and you will see that they are as 
small as gnats. I likewise send two larger flies (I 
think, male and female) hatched from maggots taken 
from the hearts of plants. 
If any of your scientific friends will be good enough 
to say to what order these flies belong, and if anything 
can be done to guard the plants against the destruction 
they produce, all Carnation and Pink growers will be 
grateful. 
I have grown Carnations 
and Pinks for a great 
number of years, both in 
Lancashire and the midland 
counties, and have always 
been troubled with the 
maggots, which are in the 
hearts of the plants, but I 
never saw anything of those 
which are found in the 
leaves until I came to reside 
here. — James Thurstan, 
Finsbury House, Fdehmond 
Road, Cardiff. 
[We have now received 
three different flies said to 
have been taken from the 
leaves or stems of Carnations. 
They all belong to the order 
Diptera, and those you 
sent us belong to the family 
Muscidte, We are con¬ 
vinced on close examination 
that the smaller of the 
two enclosed with your notes 
is Phytomyza nigricornis, 
a small black fly that 
infests various species of 
Chrysanthemums, Cinerarias 
and other Composites. One 
remedy is to collect all 
the leaves that show the 
presence of the miner and 
burn them. Another is to 
syringe the plants occasion¬ 
ally with weak tobacco- 
water or soap-suds, so as to 
render the foliage distasteful 
to the female flies, and pre¬ 
vent them from laying their 
eggs there. This latter 
remedy would also apply to 
larger flies that give rise 
to the Carnation Maggot 
proper. We received a fly 
about twice the size of the 
larger one you sent, but 
it was smashed coming 
through the post. Evidently 
there are several of the 
Diptera that attack Pinks and Carnations.— Ed ] 
Cactus Dahlias, Centenary and Mar¬ 
chioness of Bute. 
We are in receipt of two beautiful Dahlias of the class 
known as Cactus, from the fancied resemblance of the 
flower-heads of Juarezi, the original type, to a species 
of Cactus, or more properly speaking, a Cereus or 
Phyllocactus, to which the comparison is by no means 
inappropriate. Mr. J. T. West, Cornwalls, Brentwood, 
who sent them, is well known for his skill as a culti¬ 
vator and the exhibits he annually makes of this 
popular class of flowers. Centenary belongs to the 
large-sized type, and is certainly a handsome kind for 
garden decoration. There is, however, a tendency 
to raise varieties with small flowers, representing a 
Pompon Cactus type, and they will be most useful for 
cut-flower purposes. The florets of Centenary are 
elongated, narrowed to a point nearly flat, and two¬ 
toothed at the tip. They are also of a bright crimson- 
red or brilliant scarlet, and give the head, as a whole, 
a bold and conspicuous appearance. Marchioness of 
Bute is considerably smaller, and somewhat after the 
style of Charming Bride, but much paler. The florets 
are elongated, but much more bluntly pointed than 
Centenary, and white, tipped with pale rosy purple, or 
suffused there to a greater or less extent. 
- »3 = < -- 
DENDROBIUM BIGIBBUM. 
It is matter for regret that this beautiful Australian 
Orchid is so difficult to grow and flower satisfactorily in 
this country, for large importations of it have been 
made and mostly lost. A few cultivators succeed in 
growing it very creditably ; but, as a rule, failure is the 
result, or at most but a few straggling blooms are pro¬ 
duced on still fewer spikes, and the stems also dwindle 
away annually. Our illustration was prepared from a 
photograph of a plant grown by Captain Broomfield, of 
Sydney, N.S.W. The photograph was sent home by 
Admiral Fairfax to his gardener, Mr. Yea. The plant 
bore thirteen spikes, having, in the aggregate, sixty- 
seven flowers fully expanded, while nineteen other 
DENDROBIUM BIGIBBUM. 
spikes were showing for bloom. One stem alone bore 
twenty-five blooms, and was 2 ft. 7 ins. long. The 
length of the stems in this country does not usually 
much exceed 15 ins., and are generally very slender— 
say, about the thickness of a writing pencil, or even 
less. The flowers are of a beautiful magenta-purple, 
with a darker lip, but the particular shade is liable to 
variation. The specific name refers to the double 
gibbosity of the lip just above the spur, and with the 
exception of D. Phaltenopsis, there is no other Dendrobe 
like this species in cultivation. 
-- 
ASTERS AT CHISWICK. 
A large collection of China Asters have been grown 
on trial this year in the gardens of the Royal Horti¬ 
cultural Society at Chiswick, and all through the month 
of September presented a very gay appearance. Having 
on previous occasions given copious notes, with illus¬ 
trations, on the collections of Asters on trial there, we 
here confine ourselves to a few remarks on some of 
the most striking or meritorious kinds we noted 
recently. A strain called German Emperor, and of the 
Chrysanthemum type, is nntable for its dwarf and 
floriferous character. The plants are about 6 ins. high, 
but a few of them run up to 12 ins., and are close and 
bushy, bearing large pale or dark blue, rose, purple, 
lilac, and white flowers. The New Victoria is a strong- 
growing strain, varying from 12 ins. to 15 ins., and 
produces large heads of self-coloured or striped florets 
in great abundance. The Improved Dwarf Pyramidal 
Bouquet forms bushy plants about 9 ins. in height, and 
the small flower heads are of various bright colours, 
some of them being intense crimson. The Pieony- 
flowered Globe grows about 1 ft. in height, and pro¬ 
duces medium-sized heads of variously-coloured self or 
striped blooms. Like the above-mentioned, it is notable 
for its floriferous character. 
A distinctly bi-coloured race is rather striking, from 
the fact that the centre of the head is occupied with 
florets of a different colour from those forming the 
circumferential band. The French Cockade, or as the 
French write it, Cocarde, has the central portion of the 
head white, while the outer 
portion varies with rose, 
red, or blue, as in other 
strains. New Imbrique 
Pompon has smaller rose, 
purple and blue heads, with 
a white centre, and like the 
above, is somewhat novel 
and pretty. The best 
double new German Lilliput 
does not seem quite fixed, 
but many of the plants bear 
rose or purple heads, with 
a white band round the 
circumference when fully 
expanded, thus reversing the 
colours as seen in the French 
Cockade. 
Some of the quilled kinds 
are also very beautiful and 
quite distinct from the flat- 
petalled types, as in the 
case of the Lilliput strain, 
the plants of which are 
pyramidal, bushy, and about 
12 ins. in height, bearing 
a great profusion of small, 
elegant, variously-co loured 
blooms that would be very 
serviceable for cut - flower 
purposes. The Italian 
strain named Lilliput grows 
from 12 ins. to 15 ins. in 
height, forming beautiful 
pyramidal bushes, but it 
seems later than any other 
kind, for a few only of the 
terminal heads were expanded 
in the second or third week 
in September. The double 
German Hedgehog bears 
medium-sized heads of rigid- 
looking quilled florets of 
various bright colours, and 
the stems grow from 12 ins. 
to 15 ins. in height. A 
remarkably strong-growing 
kind is that named Dobbie’s 
Globe, varying from li ft. 
to 2 ft. in height. Each 
plant gives off numerous very long branches, bearing a 
single head only, and this is more than semi-globular, 
quilled with closely-arranged florets, and is so heavy 
that they bend the branches and assume a drooping or 
nodding position. On this account the plants are 
graceful enough, but lose in the combined effect 
produced by other strains with a more compact in¬ 
florescence. The size of the heads would, no doubt, 
have a telling effect when cut for the exhibition table ; 
they are of various colours, often margined with a line 
of white florets. A great extent of ground is covered 
with Asters, the varieties of which are too numerous 
to be mentioned here, and they certainly merit attention 
by those interested in this class of plants. 
Plumbago Larpenta:.— During the stormy month 
of October, this Chinese species annually puts in an 
appearance, and looks very gay indeed, provided there 
is an occasional fine day, or even an hour or two of 
sunshine. The tender and easily destructible nature of 
its flowers reminds us of the flies that are tempted 
forth on similar occasions ; but as a succession of bloom 
is produced for many days together, the plant is a 
desirable one for the rockery at this season. 
