264 H. MARSHALL WAED. 



If, howevei'j further criticism results iu the overthrow of the 

 hypothesis brought forward at the conclusion, we may 

 nevertheless hope that some service is rendered in arranging 

 the facts, and drawing attention to the necessity of employing 

 physiological as well as morphological considerations in the 

 attempt to construct a phylogenetic system of the Fungi. In 

 the last case we may at least succeed in attracting more atten- 

 tion to the direction in which modern research in this region 

 is impelling the more thoughtful biologists, and so call forth 

 confirmatory evidence or criticism of unseen fallacies. 



It we neglect a few isolated observations as having led to no 

 general views on the subject, we may regard Pringsheim's 

 discovery of the sexual organs in the Saprolegnise in 1858^ 

 as the starting point of our knowledge of the sexuality of the 

 Fungi. This observation was made at a time when attention 

 was being drawn particularly to the sexes of the Algse by the 

 researches of Thuret, De Bary, Cohn, Nageli and others ; and 

 the Saprolegniae were then, and for a long time afterwards, 

 regarded as Algse. 



Since that time numerous cases of the occurrence of sexual 

 organs have been described among other Fungi, chiefly by the 

 labours of De Bary and the school of cryptogamic morphology 

 practically established by him and his pupils. 



With De Bary's brilliant researches on the Ascomycetes,^ 

 and especially the Erysiphese,^ a point was reached where a 

 definite opinion on the sexuality of the Fungi became accepted ; 

 and the conclusions drawn from the study of Sphserotheca, 

 Eurotium, and Peziza led to the view that the fruit-body of 

 a higher fungus results from a process of fertilisation preceding 

 the development of asci, and that Hofmeister's supposition that 

 the asci are sexual organs was to be abandoned. 



In 1871 Janczewski^ described the sexual organs in As co- 

 bolus furfuraceus. Other researches by Baranetski, Gil- 



1 Sachs, ' Geschichte der Botanik.' 



2 « tJber die Fruchtentwickelung der Ascomyceten,' 18G3. 

 8 c Beitrage zur Morph., &c., der Pilze,' R. iii, 1870. 



* ' Bot. Zeitg.,' 1871. 



