Studies in the Morphology and Anatomy of the 
Ophioglossaceae. 
II. On the Embryo of Helminthostachys. 
BY 
WILLIAM H. LANG, M.B., D.Sc., F.R.S. 
Barker Professor of Cryptogamic Botany in the University of Manchester. 
With Plate III and nine Figures in the Text. 
T HE embryology of the Ophioglossaceae 1 is of peculiar interest on 
account of the variety in type of embryo within the group. The 
developmental story is pretty fully known for Botrychium lunaria and 
B. virginianum , in which the embryo has no suspensor, and the salient 
facts are recorded for B. obliquum , in which a suspensor was discovered by 
Mr. Lyon. For Ophioglossum the embryology is known in O. vulgatum , 
O. moluccanum , and O. pendulum. The embryos of these species, while 
agreeing in having no suspensor, exhibit considerable differences in detail. 
The present paper is concerned with the embryology in the third genus of 
Ophioglossaceae, and is thus supplementary to a paper published in this 
Journal in 1902, which dealt with the prothallus and young plants of 
Helminthostachys zeylanica. 
In my earlier paper no attempt was made to deal with the embryogeny 
since the material seemed so inadequate. One section of a mature embryo 
was figured and briefly described, and it was remarked with regard to the 
earlier stages, £ A number of archegonia had apparently been simultaneously 
fertilized on a few of the prothalli which were attached to young plants. 
The preservation of the arrested embryos, which were present in addition to 
the plant, was not good enough to make a study of the segmentation 
possible. It was, however, clear that, as in Botrychium , the embryo soon 
becomes deeply seated.’ 2 The similarity of these young arrested embryos 
to the young embryos of Botrychium obliquum figured by Bower 3 from 
Mr. Lyon’s preparations suggested that the embryo of Helminthostachys 
i 
1 The recent full summaries and discussions of the facts by Prof. Bower (Land Flora, 1908) and 
Prof. Campbell (The Eusporangiatae, 1911) make detailed reference to the literature unnecessary. 
2 Lang, Ann. of Bot., xvi, 1902, p. 40. 3 Land Flora, Fig. 266, p. 472. 
[Annals of Botany, Vol. XXVIII. No. CIX, January, 1914.] 
C 2 
