illustration, but we will let it pass; and as regards the former part of the cry, I do not know that the plant-doctor can expect the cultivator to be initiated in the aetiology of the disease any more than the physician expects the parent to understand the biology of the typhoid bacillus. That both the cultivator and the parent would be the better for a real knowledge of the disease in either case must be admitted--nay insisted on, provided the knowledge _is_ real--but we have to deal with facts, and it is a fact that the clients of both doctors are impatient of the details of the case. Now, of course, I am aware that no short cut or "royal road" to science exists, and if a man is going to train up trees or other plants, he ought to know all about them in health and in sickness, in youth and in old age, and he ought to learn everything about the soil they grow in, the air that surrounds them, the enemies that beset them, and all the multifarious relations of these one to another; but when I look at my boy and reflect how much his nurse, his schoolmaster, his tutor, his doctor, and his parents _ought_ to know successively and simultaneously about him in sickness and in health, and about his surroundings, etc., I begin to wonder whether there is not after all something to be said for the cultivator's point of view. Moreover, the cultivator knows a good deal about his plants which I do not know, and although I should much like to know it, his plea of want of time rings in my ears and the conviction strikes home that one ought to try and meet his views, and tell him something about disease as manifested in plants without insisting on his becoming a professional mycologist, entomologist, agricultural chemist, and philosopher. Of course, beyond a certain point, it is his lookout how much the information is worth, and its educational value--a very different matter--is sure to suffer from any restrictions imposed on the treatment of the subject; but if the theme of disease in plants, treated from a general point of view--I was about to write "treated in a popular manner," but that is impossible until physiology and mycology are more widely taught--enables him to understand better the questions he puts to himself, and, still more, if it stimulates him to enquire further into the inexhaustible field of science glimpsed at, something may come of it.