than the observations themselves. Thus, judging from his figures, he saw the contents of the pollen grain, the appearance of which, under the conditions of observation, might easily suggest the idea of an embryo. Also he noticed that the pollen grains burst in a little while when placed in water, a phenomenon which was rediscovered 138 years later[1], and he therefore thought that a similar bursting, with a consequent setting free of the embryo, would take place on the wet stigma of the lily, for example.
Taxonomy.
One of Hill's more interesting works in this branch of Botany is his British Herbal[2]. In it are described a large number of plants which are illustrated by 75 copper plates engraved by various artists. None of these plates are of outstanding excellence, indeed many of them are very poor, and their quality is uneven. Those in the folio consulted by the present writer were ruined by being coloured.
The plants described are arranged on a system which is not altogether without interest as it, in a small degree, foreshadows later systems. It may be indicated by giving the characters of the first four classes.
Class 1. Plants whose flower consists of several petals, with numerous threads in the center, and is followed by a cluster of naked seeds.
Class 2. Plants whose flower consists of several petals, with numerous threads in the center, and whose seeds are contained in several pods.
Class 3. Plants whose flower consists of a single petal, and is succeeded by several capsules.
Class 4. Plants with the flower formed of a single petal, plain, and of a regular form and succeeded by a single capsule.
It will be seen that Hill relied much on the characters of the corolla and the gynaeceum. But the chief interest in this work
