THE NATURE AND ORIGIN OF THE BINUCLEATED 
CELLS IN SOME BASIDIOMYCETES. 
SUSIE PERCIVAL NICHOLS. 
INTRODUCTION. 
Rees (20) was among the first to attempt a careful study of 
the mycelium of the Basidiomycetes with reference to the ques¬ 
tion of the origin of the carpophore. By making artificial cult¬ 
ures of Coprinus stercomrius in dung decoction on slides he was 
able to observe the formation of erect short hyphae on which 
he believed sexual cells, spermatia and carpogonia were borne. 
He also believed that he found a spermatium fused with a car- 
pogonium. After fertilization, branches arise from the base of 
the carpogonium which developed into the carpophore. 
Yan Tieghem (25) also germinated the spores of Coprinus 
stercorarius and radiatus in dung decoction and studied the de¬ 
velopment of the carpophore. In his first paper he agreed with 
Rees. He found the swollen end cells on the lateral branches 
of the mycelium. These “carpogones” usually terminated in a 
papilla with which the spermatia fused. The carpogone then 
divided into three cells, the two lower developing a system of 
lateral branches which curve around and enclose the terminal 
cell. Their further development in slide cultures was prevented 
by lack of nutriment. But by observations made on larger cult¬ 
ures they were seen to be the beginnings of carpophores. Later 
Yan Tieghem reversed this opinion. * 
Brefeld (3, 4) grew mycelium of Coprinus stercorarius from 
single spores in dung decoction and figures a series of stages in 
