8 
THE AUSTRALASIAN JOURNAL OF PHARMACY. 
3. Plant Pathology, or the diseases of plants. 
4. And reference will finally be made to the use of the Microscope, for, while 
that instrument is by no means confined to Botany, it is largely used in 
connection with it. 
1. The Physiology of plants, with its more accurate determinations and more 
reliable results in modern times, has enabled us not only to understand many of the 
hitherto hidden and obscure processes of plant life, but to express our knowledge in 
terms of physiology rather than in those of morphology or structure. 
The organs are no longer regarded mainly as possessing certain characteristics of 
form and structure, but more essentially as a means for doing certain kinds of work, to 
which purpose the structure necessarily conforms. The purpose, in fact, explains the 
particular kind of structure, and, while morphology deals with the organs or apparatus 
concerned in certain processes, such as nutrition or reproduction, physiology is concerned 
with the processes themselves. 
Thus the stomata, or breathing pores, of a plant put the interior into communication 
with the outer air at certain points. It is the province of physiology to investigate 
their use, why they are usually placed on the under side of the leaf, the quantity and 
quality of the materials passing out and in, and the conditions under which they open 
and shut by means of hydrostatic pressure. It is the business of morphology, on the 
other hand, to describe the stomata, to show how their structure permits of their being 
opened, or closed by hydrostatic pressure, and how certain forms could alone conform to 
such regulations. 
A physiological classification of organs brings the whole range of plant life, from 
the lowest to the highest, under one all-embracing principle, and that is a great gain, as 
well as a great simplification, to botanical science. 
2. Plant Histology deals with the tissues, and, when these are viewed in relation to 
their function and not merely to their form, just as in the case of the organs, then 
their study is completely transformed from the dead, dry bones of structure to a living 
and animated power. Bach part is then seen in its organic connection with the whole, 
and along with the greatest subdivision of labour there is perfect harmony of action 
between the different parts. One part has to protect, another to strengthen as a 
skeleton, some for nutrition and circulation, some for respiration and excretion, and 
others for reproduction ; so that, in this way, an organic whole is constituted out of its 
component parts* Here again the study of the tissues is invested with a living interest, 
and saved from degenerating into a mere matter of section-cutting and staining, and 
deciphering of complex patterns, as is too often the case. 
3. Plant Pathology , or plant disease, possesses an interest not merely for the 
agriculturist and horticulturist, but for the botanist, who thereby gains an insight into 
the normal as well as abnormal conditions of plant life. Of late years considerable 
activity has been displayed in this department, and a fuller knowledge of the causes and 
the products of disease in plants, and of the repair of injuries, will tend to throw light 
upon the conditions necessary for a healthy growth. I he normal and abnormal 
conditions of fife, like good and bad weather, are but different stages of the same cycle, 
and the one serves to throw the other into strong relief. 
So, whether studying plants in the gross or the minute as to their organs or tissues, 
or whether in health or disease, it will be observed that the processes at w r ork receive 
first consideration, and the means whereby these processes are carried on grow out of the 
former, and are seen to be necessary adjuncts. It is further to be noted that, in seeking 
for the uses of any special part or product to a plant, we may obtain some clue as to 
their possible use to us either in medicine or the arts. 
4. The use of the Microscope in Botany will only be touched upon so far as to show 
that in Pharmacy it may often render valuable assistance — for instance, in the detection 
of adulterations, as well as in the accurate determination of specimens. A single 
example in the writer’s own experience may be quoted. A sample of saffron was being 
examined, which is well known to consist of the dried stigmas of species of crocus, and 
the rolled-up florets of a composite were detected at once, similar in colour to the real 
saffron, and difficult of detection by chemistry, but revealing under the microscope, at a 
glance, the different parts of perfect yet minute florets. The working and proper 
manipulation of the microscope is, indeed, indispensable to anyone wishing to realise for 
himself the variety of products stored up in plants which are used for medical purposes. 
