366 Wulist: BRANCHED PROTHALLIA 
bearing other prothallia.’’ Lagerburg (’06) figured a slightly 
branched filamentous male gametophyte of Pteridium aquilinum 
(L.) Kuhn. Pace ('10) described branched filamentous prothallia of 
an unknown genus, and Black (’15) observed extensive branching 
among the filamentous prothallia of Onoclea sensibilis L. which had 
grown in a submerged condition in cultures of distilled water. 
Cc 
Fic. 1. Branched prothallia of Onoclea sensibilis Ly Kas: 
MATERIAL 
The branched prothallia described in this paper occurred in 
cultures which had been made for the study of the comparative 
length of the filamentous stage in various genera of the Polypodi- 
aceae. The genera which showed a tendency to branch were the 
following: Adiantum, A splenium, Camptosorus, Onoclea, Phegopterts, 
Polypodium, Pteridium, Scolopendrium, Woodsia and Woodwardia. 
The spores of these various genera were obtained from several 
sources. Those of Adiantum were secured from the greenhouse 
of the botanical department, Cornell University, and those of 
Phegopteris came from a lawn in Ithaca, New York. The spores 
of Camptosorus and Scolopendrium were collected in eastern New 
York by Mr. Ten Eyck Burr; while those of Asplenium, Onoclea, 
