Page:History of botany (Sachs; Garnsey).djvu/225

 volumes and the figures large folios; the abundance of forms in the Thallophytes proved to be so great that many botanists devoted their whole attention to them, many collected and described only the Algae, others only the Fungi and Lichens. It is true that a deeper insight into the connection of these forms of life with one another and with other plants was not to be obtained in this way; still an empirical basis was formed for a knowledge of the Cryptogams, such as had been established for the Phanerogams by the herbals of the 17th century. All forms open to observation were named and arranged in one way or another; and there was no difficulty in understanding what form was meant, when names, or tables and figures, were cited from the various books. Of such works, those of Agardh, Harvey, and Kützing on the Algae, those of Nees von Esenbeck , Elias Fries, Léveillé, and Berkeley on the Fungi, and especially Corda's elaborate work on the latter plants are the most valuable.