VOLUME XLII . NUMBER 4 
BOTANICAL GAZETTE 
OCTOBER, 1906 
THE DEVELOPMENT OF AGARICUS CAMPESTRIS.* 
Gro. F. ATKINSON. 
(WITH PLATES VII-XI1) 
IN some respects the history of the study of the Hymeniales does 
not present the same progress which can be seen in the other groups 
of fungi, or indeed in nearly all other groups of plants. The earliest 
period, that of the study and classification of species and genera, 
presents in the main the same aspects which have been characteristic 
of the early study of all plants; but the progress made up to the present 
time is not in proportion to the time and energy expended, due to 
certain difficulties, some inherent in the nature of the plants them- 
selves, and others due to the lack of an adequate knowledge of their 
anatomy and development. 
The second period, that of the study of the morphology and 
development, began more than half a century ago. It is true that in 
the early part of the 19th century, nearly a century ago, quite an 
elaborate theory of the development of the Hymeniales, especially 
the Agaricaceae, was evolved by NEES von EsENBECK.’ But his 
theory, embellished as it is with his philosophical ideas of the evolu- 
tion and metamorphosis of these plants from the puffballs and truf- 
fles; in which he was evidently influenced by the philosophy expressed 
in the Vorwort of GorTHE’s Farbenlehre, that in a book dealing with 
* Contribution from the Department of Botany of Cornell University. No. 110. 
Paper presented before Section G, of the A. A. A. S., at the New Orleans meeting. 
* Das System der Pilze und Schwimme, ein Versuch von Dr. C. O. NEES VON 
ESENBECK, I-XXXVI, 1-329, 44 plates, Wiirzburg, 1816. See also NEES VON EsEN- 
BECK, Plantarum Mycetoidarum in Hort. Bonn. obs. evolutio. Nov. Act. Natur. Curios, 
16: pars 1, 1832, for development of Agaricus volvaceus. 
241 
