458 Umversity of California PuiUoations m Botany 



IV. GEOWTH OF THE SPOROPHORB 



1. DEVELOPMENT IN GBNBBAi 



The development of the sporophores was early looked to for an 

 explanation of the peculiar pairs of hymenial plates which charac- 

 terize ScUzophyllum. Fries (1821) believed that they arose as ordi- 

 nary gills and were split by drying. This view was agam brought 

 forward by Fayod (1889), and still later by Buller (1909). Hoffman 

 (1860) believed the sporophore to be divided into a series of lamellar 

 systems, considering all the secondary gills to belong to the primary 

 hymenial plates which enclosed them. His view was adopted by Winter 

 (1884). 



Adams recently (1918) made the statement that each lamella con- 

 sists "of the adjacent walls of two gill cavities which originate endo- 

 genously as tubes in the substance of the carpophore. The gill cavities 

 (tubes) split along their lower edges and lamellae are thus completed." 



In Hasselbring's (1907) paper on "Gravity as a Form-Stimulus 

 in Fungi" appears the statement that "they [the young sporophores 

 of 8. commune] appear as small outgrowths resembling simple forms 

 of Clavaria, and attain a; length of about one centimeter. Early in 

 their development a cup-like depression appears at the summit, and 

 within this the rudimentary lamellae are formed, radiating from the 

 center. ' ' 



Two distinctly opposed views have, then, been advanced by Hassel- 

 bring and Adams. Adams held that the "gills" originated endogen- 

 ously as the sides of horizontal tubes which later ruptured at the 

 lower edge and exposed the hymenium, while Hasselbring claimed that 

 the "gills" arose exogenously upon the surface of an apical cup-like 

 depression. It seems unlikely that Buller and the previous writers 

 had access to sporophores in the first stages of development, for they 

 made no statements concerning the early appearance of the fruit 

 bodies. Both Adams and Hasselbring, however, grew the sporophores 

 through all their stages in the laboratory. Adams grew his in flasks 

 on agar media from "immature carpophores collected in the field." 

 Hasselbring caused them to grow from ' ' pieces of a maple branch con- 

 taining the mycelium — placed on a klinostat. ' ' 



The writer has had an opportunity to study the origin and devel- 

 opment of the sporophores both on a log of Umiellularia caUfornica 



