On the Development of the Spores of 
Helminthostachys zeylanica. 
BY 
RUDOLF BEER, B.Sc. 
With Plates XI and XII. 
T HE writings of Goebel 1 , Holtzman 2 , Campbell 3 , and Bower 4 have 
made us familiar with the early history of the sporangium of the 
Ophioglossaceae. The actual structure of the spore, however, and the 
later stages of development, leading up to the establishment of that 
structure, have, hitherto, only been very imperfectly described for any 
member of this Order. Recently the publication of two papers, by 
Cardiff 5 and Stevens 6 respectively, have added considerably to our 
knowledge of certain stages in the history of the spores of Botrychium , 
but we are still far from having a complete account of even this genus. 
Through the kindness of Prof. F. W. Oliver I have had the oppor- 
tunity of examining a number of fertile spikes of Helminthostachys 
zeylanica which had been preserved in spirit. 
Although many important cytological details can only be determined 
with certainty by the study of material which has been specially fixed for 
the purpose, it was thought that the following notes might not be without 
their interest. 
The first stages in the development of the sporangium of Helmintho- 
stachys zeylanica have been followed by Bower, who found the sporangium 
to be derived from a single superficial cell. 
The first periclinal division of the cell defines the sporogenous from 
the protective portions of the sporangium ; ‘ the sporogenous mass 
1 Goebel, 4 Beitrage zur vergleichenden Entwickelungsgeschichte der Sporangien/ Bot. Zeit. 
1880, Bd. xxxviii. 
2 Holtzman, * On the apical growth of the stem and the development of the Sporangium of 
Botrychium Virginianum / Bot. Gazette, 1892, vol. xvii. 
8 Campbell, 4 Mosses and Ferns/ 1895. 
4 Bower, 4 Studies in the Morphology of Spore-producing members/ II, 1896. 
5 Cardiff, 4 Development of Sporangium in Botrychium / Bot. Gazette, May 1905, vol. xxxix. 
6 Stevens, ‘Spore Formation in Botrychium Virginianum / Annals of Botany, October 1905, 
vol. xix. 
[Annals of Botany, Vol. XX. No. LXXVIII. April, 1906.] 
N 
