70 
HOPS. 
frame need not be very large, for it is only wanted in the early stages 
of growth. In this way it would be possible to make out quite surely 
whether attack occurred, and if so whether it was from wingless 
females, which had lived through the winter and laid eggs in the 
spring, or whether it was from the so-called lice coming up from eggs 
which had been laid in the ground. 
We might, however, learn much (if not all) we need during the 
coming season, if those who have the opportunity would watch the 
bines on a few hills as soon as they begin to shoot, giving a careful 
look every day (or even every two or three days), so as to be able to 
learn without doubt whether, when the very first Aphides appear, they 
are in the form of “lice” (that is, wingless) or of “ fly ” (that is, 
winged). 
If they appear as lice it would seem impossible that they can have 
come from anywhere but some shelter in or near the hill where they 
have been hatched ; if they appear as fiy we cannot but suppose 
they have come on the wing from elsewhere; for the “ fly ” 
must have fed in its previous state as “louse,” and if it had 
done this at the roots in the hill it would have been seen before this 
time. 
If the attack does not begin from eggs or Aphides in the ground 
around the stool of the Hop, the next question is, What part Plum 
trees or the Sloe bashes play in the matter ? 
It is distinctly stated by three well-known German naturalists 
that the Hop Aphis, the Aphis humuli , is to be found on Plums or 
Sloes. One (Kaltenbacli) states that he himself has found it on Sloe 
bushes in May; another (Taschenberg) that it is found on Sloe, and 
therefore Sloe bushes ought not to be left near Hop grounds; and a 
third (Koch) states that this Aphis is to be found in May in great 
numbers on the young shoots and beneath the leaves of the Plum and 
Sloe, and that in the month of June these Aphides (that is the 
A. humuli) leave the Plum leaves and betake themselves to the Hop. 
This view was also taken by one of our own naturalists, Francis 
Walker, and it well deserves proving or disproving, for the notes 
given from our own Hop grounds of Hop Aphis being first observed in 
the winged state make it appear very likely that the creatures may have 
flown from some neighbouring feeding ground. 
It is observed by Mr. Hart, of Kingsnorth, “It is generally con¬ 
sidered that the Aphis first appears on the Hop in the winged form. 
The ‘lice,’ as they are termed, are never seen till after the ‘fly’ has 
appeared.” 
Mr. Whitehead also informs me that they are supposed always to 
appear first as Flies , but that he saw wingless Aphides in April last 
on the Hop plant, before the others were seen. 
