“302 QUEENSLAND AGRICULTURAL JouURNAL. [1 Aprin, 1898. 
friend, the eminent botanist, Rey. M. J. Berkeley, who described and figured it 
in the Gardeners’ Chronicle, 6th November, 1869, giving it the name Hemileia 
vastatric. Its most noticeable feature to the unaided eye consisted of circular 
‘blotches like ironmould on the under surface of the leaves, and from this fact the 
natives of Kandy soon gave it the name of “‘ Yakada rogaya” (iron disease). 
It spread with fearful rapidity. Without doubt, the coffee plantations of 
the island were in a condition to harbour the guest so unwelcome to the 
‘planters. 
In 1866-7-8 the average yield of coffee in Ceylon was 4°28 ewt. per acre ; 
in 1872-3-4 it had fallen to 2°93 cwt. per acre; and in 1878 the average was 
below 2 cwt. per acre. 
Let us look at the tiny plant capable of working such mischief, and so 
fix it in our minds that if ever by evil chance the coffee-grower shall find it in 
his plantations, he may be able to recognise it with some degree of certainty. 
The figure in the top right-hand corner of the illustration shows what the 
entire plant is like when magnified 200 diameters. We shall see presently how 
youcan detect it withouta microscope. Every person who has to do with plants 
should carry a good lens. He will find that it will open up to him quite new 
ideas on the subjects of the insect and fungoid pests by which he is, and will 
ever be, surrounded. One of the gardeners in these Gardens, who had worked 
all his life amongst plants, was shown the other day the eggs of scale insects 
through a strong glass. He was astounded, and went about his work witha 
far clearer idea of the task before him than any amount of reading would have 
conveyed. ; 
The Rey. R. Abbay, an enthusiastic botanist, studied the Hemileia plant 
in 1877 ; and in 1878 the present chief of the Royal Botanic Gardens at Kew, 
‘Mr. W. T. Thistleton Dyer, M.A., F.L.S., communicated to the Linnean 
Society of London a clever paper on the subject by Mr. Abbay. This 
gentleman succeeded in growing the spores of the tiny fungus in England, 
though they had been sent from Sumatra to Ceylon, and from thence to 
England in:the dead of winter. This will give an idea of the tenacity of life 
of the seeds—or, to be technical, the spores—of this fungus, which botanically 
belongs to. the same general family as the ordinary mushroom. If you look 
again at the figure in the top right-hand top corner, you will see that the tiny 
plant bears a rather close resemblance to an ordinary puft-ball fungus, such as 
you have often found in the paddocks. 
Now you know, or if you do not it is as well to learn, that almost 
every leaf has dotted over its surface an immense number of breathing-pores, 
called stomates or “little mouths.” These are the doors of communication 
between the Jeaf-cells and the outer air. It is as essential to the plant that these 
stomates should be free as it is to you that your lungs and mouth should be 
-in good working order. fi 
These stomates (the English terminations are used in order to avoid 
confusion, for it is assumed that you have been too busy to read up this 
subject) vary in their condition according as they are acted upon by external 
influences, as well as by influences connected with the growth of the plant. 
_The seed (spore) of the tiny fungus falls on a leaf, and attacks the ieaf 
through the breathing-pore, grows through it in fact, and soon assumes the 
appearance shown in the sketch, where the mycelium (as the thread-like 
bodies, corresponding in some degree to the roots of other plants, are called) 
are shown shooting from the base of the flask-shaped body which forms the 
main body of the fungus. On the top you will note a spreading tuft. This 
is the cluster of sporanges, or spore-cases, which grow outside the lower surface 
of the leaf, the narrow neck ot the flask-shaped fungus passing through the 
breathing-pore. All the rest of the fungus is embedded in the substance of 
the leaf between the upper and Jower skin, and myriads of breathing-pores are 
closed up. If you remember how sickly your pot plants become when you 
allow the Mrantlaneeniees to become choked with dust, you will realise how 
injurious to the growth of the host plant this closing of the breathing-pores 
