134 
THE FLORIST AND POMOLOGIST. 
[ June, 
THE AUEICULA DISEASE. 
[T the first May meeting of the Eoyal Horticultural Society’s Scientific 
Committee, the following communication on this subject was read:— 
The mystery attending the Auricula disease is solved. At Mr. D’Ombrain’s 
suggestion, Mr. J. T. D. Llewelyn, of Unis-y-Gerwn, Neath, South Wales, 
has been kind enough to bring me a plant with the disease well established on it, 
and bearing plenty of a woolly aphis round its collar and about its roots. This 
aphis was in two stages—some individuals being provided with a woolly excre¬ 
tion, and others without it. Those without it corresponded in general appearance 
with both the figure and description of Trama radicis^ given by Koch in his 
monograph of Pflanzenlause. It has the same form, the same minute eyes 
adapted to its semi-subterranean mode 
of life, the same lateral insertion of 
the legs, (fee.; but on more minute 
examination, there are some trifiing 
differences, which may perhaps warrant 
us in considering this as a new species, 
the more so that, neither in Koch’s 
description, nor in Walker’s in the list 
of homopterous insects in the British 
Museum (p. 1,061), nor in Westwood’s 
description of Ehizohius heliantheini 
{Pr, Ent. Soc.^ Jan. 2, 1843 ; Ann. 
Mag. Nat. Hist.., xiv. 453), which 
Walker gives in his List, but not in 
his Supplement, as a synonym of 
Trama radicis., is there any mention 
made of any woolly secretion—this, 
however, being a thing that is not 
always present, or perhaps it would be 
more correct to say, not present at all 
times or ages, may have to be looked 
at with caution as a specific distinction. 
The colour of the body in the Auricula- 
insect is a little greener than in Trama radicis., which is spoken of as a louse- 
coloured white, and the legs and antennae are olive-brown, whereas in T. radicis 
they are concolorous. Colour, however, does not go for much. If we could trust 
to the description of the antennae by the different authors, this must be a distinct 
species, but I am afraid we cannot. Koch says they are seven-jointed ; Westwood 
and Walker, six-jointed. When placed on a microscopic slide the antenna cer¬ 
tainly seems to be only six-jointed, but when the living aphis is examined with a 
lens, there is seen in addition a small bulb from which the antennae take rise, 
which may be either an actual joint or a tubercule. Koch has obviously con- 
Trama auriculae. 
