A STUDY OF REGENERATION: AS EXHIBITED BY 
MOSSES 
FRED DE FOREST HEALD. 
(WITH PLATES XIX—XxX) 
I. INTRODUCTION. 
TuHaT the sexual generation of the bryophytes is endowed 
with a remarkable power of regeneration is a well-known and 
oft-stated fact. The extent to which this is true for the liver- 
worts has been shown by the investigations of Véchting’ “Uber 
die Regeneration der Marchantieen’’ and of Schostakowitsch? 
“Uber die Reproduktion und Regenerationsercheinungen bei den 
Lebermoosen.”’ As far as the mosses are concerned, the gen- 
eralizations have been based upon scattered and isolated obser- 
vations by Schimper, Goebel, and others, and not upon any 
detailed investigation. The present work has been carried out 
with the intention of showing to what extent these generaliza- 
tions in regard to the vegetative reproduction from stem and 
leaf are true, and also to throw some light on the physiology of 
regeneration. 
Before proceeding with theresults of my own investigations, 
brief mention will be made of some of the observations pre- 
viously recorded. 
II. HISTORICAL. 
The first record of the formation of protonemata by the 
leaves is by Kiitzing3 for Bryum pseudotriquetrum. The leaves 
produced an abundant protonema growth and after a period of 
eight weeks, buds appeared. 
Schimper* obtained a growth from the basal portion of 
"Jahrb. f. wiss. Bot. 16 : 367. 1885. 
*Flora, Erganzungsband 1894 : — 
3Phycologia generalis 282, 18 
*Recherches anatomique et Siphologicaus sur les mousses 19. 1848. 
1898 } 
