Page:The growth of medicine from the earliest times to about 1800.djvu/403

 (1577-1657), Boselli of Naples (1608-1679), Lower of Oxford, England (1631-1691), Vesling of Minden, Germany (1598-1649), Regnier de Graaf of Delft, Holland (1641-1673), who gained so great distinction by his accurate description of the ovarian follicles ("Graafian follicles"); and James Douglas (1676-1742), the English anatomist, who ascertained and described the precise limits of the peritoneum.

Of all the men whom I have mentioned above, Malpighi and Leeuwenhoek are probably the best known to our readers for the large number and important character of the contributions which they made to microscopic anatomy. The list of Malpighi's achievements, for example, includes the following, in addition to the demonstration of the blood in actual circulation, as already mentioned: contributions to our knowledge of the finer structure of plants; the demonstration of the minute anatomy of the skin ("rete mucosum" or "rete Malpighi"); the amplification of our knowledge of the structure of the teeth; the discovery that the lungs are composed to a large extent of terminal vesicles, the walls of which are richly supplied with blood-channels.; the demonstration that certain glands possess an acinous structure (i.e., an outlet channel springing from numerous small sacs, the whole group resembling a cluster of grapes); more complete details regarding the structure of the spleen and the kidneys ("Malpighian bodies or corpuscles"); additions to our knowledge of the structure of the white and the gray substances of the brain and the demonstration that fibres from the spinal cord pass on into the brain; the declaration that the papillae of the tongue are organs of taste and the papillae of the skin are organs of the sense of touch; and not a few other contributions of greater or less importance. During his long life Anton Leeuwenhoek (1632-1723) of Delft, Holland, made a great many additions to microscopic anatomy, some of the more important of which are the following: he was the first to discover and to describe the many varieties of Infusoria (the animalcules found in stagnant collections of water); to him is also due the credit of first observing the faceted