Harry Marshall Ward. . Vv. 
to the new Chair of Botany in the Forestry Branch of the Royal Indian 
Engineering College, Coopers Hill. The utilitarian atmosphere in which 
he found himself was not very congenial to him. But he had at any rate 
at last some sort of adequate position and a laboratory to work in, and 
here he remained—not, I think, unhappily—for ten years. He was, as he 
had been at Manchester, a successful teacher, and had the gift of 
interesting his pupils, whom he used to bring weekly to Kew during the 
summer months to visit the Arboretum. In point of research, this was 
the period of much of his most brilliant work. 
The study of Uredinez occupied Ward at intervals during his life. The 
reproductive organs are pleomorphic, and it is no easy task to ascertain with 
certainty those that belong to the same life-history. In a paper on 
Entyloma Ranunculr, published in the ‘Phil. Trans.’ in 1887, Ward for the 
first time traced the germination of the conidia of an Entyloma, and 
confirmed Winter’s suggestion that they were not an independent organism, 
but actually belonged to it. Incidentally he discussed the conditions which 
are favourable to the invasion of a host by a parasitic fungus. This raised 
the question of immunity, to which at intervals he repeatedly returned. 
About the same time he published in the ‘ Quarterly Journal of Microscopical 
Science’ the results of an investigation undertaken for the Science and Art 
Department on the mode of infection of the potato plant by Phytophthora 
infestans, which produces the potato disease. It was not éasy to add any- 
thing to the classical work of de Bary, but it was ascertained that “the 
development of the zoospores is delayed or even arrested by direct daylight,” 
and Ward’s attention was attracted to the problem, which he afterwards 
solved, of how the hyphe erode the cell-wall. 
The solution was given in 1888 in a paper in the ‘ Annals of Botany,’ “On 
a Lily Disease,’ which has now become classical. He discusses the fungus 
which produces it, and shows that the tips of the hyphe secrete a cellulose- 
dissolving ferment which enables them to pierce the cell-walls of the host. 
This ferment has since been described as cytase. He shows that its pro- 
duction would determine the passage from a merely saprophytic to a parasitic 
habit, and makes the suggestion that an organism might be educated to 
pass from one to the other. 
An admirable research (1887) was on the formation of the yellow dye 
obtained from “ Persian berries” (Rhamnus infectorius). A dyer had found that 
uninjured berries afforded a poorer colouring liquor than crushed. Gellatly 
had found, in 1851, that they contained a glucoside, xanthorhamnin, which 
sulphuric acid breke up into rhamnetin and grape-sugar. The problem was 
to localise the ferment which did the work. Ward obtained the unexpected 
result that it was confined to the raphe of the seed. 
As early as 1883 Ward had attacked a problem which he pursued at 
intervals for some years, and which was fraught with consequences wholly 
unforeseen at the time. It had long been known that leguminous plants 
almost invariably carried tubercular swellings on their roots. The opinion 
