Contributions to our Knowledge of the Anatomy of 
the Cone and Fertile Stem of Equisetum. 
BY 
ISABEL M. P. BROWNE. 
With Plates LXIV and LXV and ten Figures in the Text. 
Historical Summary. 
I N 1864 appeared Duval Jouve’s ‘ Histoire Naturelle des Equisetum de 
France ’ ; this work contained many new and important researches and 
also gave an excellent summary of the earlier literature concerning the 
Equisetaceae. In 1865 Milde published his ‘ Monographia Equisetorum ’ ; 
in 1867 appeared Pfitzer’s account of the structure and distribution of the 
endodermis in the German species of Equisetum ; this paper also contains 
excellent anatomical observations. In 1876 Famitzin and Janczewski, 
working independently, published more correct accounts of the branching 
of Equisetum ; the following year appeared a short paper by Tomaschek, 
and in 1878 one by Sadebeck on the embryology of the genus. In 1886 
Goebel published a short note on the cones of the Horsetails, and in 1888 
Buchtien gave a detailed account of the prothallus and young sporo- 
phyte. The same year Muller published an account of the leaf-sheaths of 
the Equisetaceae, written almost entirely from the point of view of resis- 
tance to mechanical strains and tensions. In this year, too, Van Tieghem 
and Douliot treated of Equisetum in their paper on the origin of endo- 
genous members, and in 1890 Van Tieghem published additional observa- 
tions on the endodermis in the genus. Two years later Leclerc du Sablon 
described the structure of the tubers, and in the following year Cormack 
investigated the nodal structure of Equisetum , describing what he believed 
to be secondary xylem. In 1893 Bower, in the first of his papers on the 
Morphology of the Spore-producing Members, dealt with certain features 
of the Equisetaceae. Campbell’s ‘ Mosses and Ferns published in 1895, 
gave a general account of the group, while in 1899 Jeffrey published a paper 
dealing in detail with the structure and affinities of the genus. In 1901 
Gwynne-Vaughan, in a short communication, suggested a fresh interpreta- 
[ Annals of Botany, Vol. XXVI. No. CIII. July, 1912.] 
