PRESIDENTS ADDRESS. 
I 
upon his business, who thinks ancl dreams of nothing but success 
in business, an altogether desirable ideal? A man whose sole aim 
is success in life is apt to become a mental if not a moral obliquity, 
and as wearisome a bore as the man who Inis no thought outside 
his profession, be that profession clerical, medical, or legal. 
It is now many years since helminthologists became acquainted 
with the life history of certain Entozoa, in which the parasite in 
one stage of its existence is embedded in the tissues of its host, 
either in the muscle, bone, liver, brain, or some such organ : while 
the other state is found in another animal in the form of a llattened 
articulated worm, whose head is anchored to the interior of the 
animal’s intestine. The host of the first named or hydatid-form is 
mostly an herbivorus animal, while the latter or tapeworm host 
is a carnivore. The eggs of the tapeworm, which are discharged in 
enormous numbers, are quite innoxious to healthy individuals of the 
tapeworm host; but if they find their way into the alimentary canal 
of the vegetarian hydatid host cause it to become alfected with the 
hydatid disease. 
A very parallel life history involving a hetercecism or change of 
host is encountered when we turn our attention to certain parasitic 
fungi, the best known instance of which is afforded by that 
terrible pest, the Mildew of Wheat. To many this may appear a 
worn-out topic, but there are certain peculiarities connected with 
this disease, and with several closely allied diseases of cereals, that 
render the whole question worthy of attention, especially from us 
who dwell in an agricultural county like Norfolk. What is known 
of the life history of the Wheat mildew fungus for certain may be 
briefly summarised as follows. As a matter of observation amongst 
the Norfolk farmers of the eighteenth century, it was known that 
the presence of Barberry bushes in the hedges of Wheat fields 
increased the tendency of the Wheat grown in those fields to become 
mildewed, and that the maximum amount of disease was to be met 
with in the immediate vicinity of the Barberries. Arthur Young, 
at the end of the eighteenth century, instituted a series of special 
observations, which by drawing public attention to this fact led to 
a Barberry crusade, whereby this shrub was almost exterminated as 
