o 
Chrysler.—The Nature of the Fertile Spike in 
Of quite different opinion is Bower, who since 1891 (3) has offered 
evidence for considering the fertile spike of Ophioglossum to be a septate 
sporangium arising on the ventral face of a sporophyll. Thus the aerial 
organ of Ophioglossum represents one of the sporophylls of the cone of 
Lycopodium. From Ophioglossum are derived the different species of 
Botrychium , which are arranged in an ascending series, and Helmintho- 
stachys takes its place as an elaborated pattern from the same origin. 
According to this view the ancestors of the Ophioglossaceae are micro- 
phyllous forms such as the Lycopods. Other writers, especially Celakovsky 
(10), have suggested a common origin for Ophioglossaceae and Lycopod- 
Figs. 1-7. Diagrams illustrating the origin of the strands which supply the fertile spike in 
Botrychium virginianum. Fig. i is from the lowest section. Xylem is shaded, phloem left clear. 
The adaxial side of the petiole is placed upward. 
iales, but none have supported the theory by any such array of evidence as 
Bower presents. 
Campbell ( 8 , 9) would give Ophioglossum a place much nearer the base 
of the genealogical tree, deriving the fertile spike directly from a sporo- 
gonium such as that of Anthoceros. An extended account of the different 
theories will be found in Bower’s monograph on the Ophioglossaceae (4). 
When the affinities of a group are subject to such wide variations 
of opinion, evidence should be sought in all quarters, and the attempt 
is here made to bring forward anatomical data which bear in no uncertain 
way upon the question. The work here described has to do chiefly with 
the origin of the vascular strands which supply the fertile spike. Although 
this has been examined in several European forms, the modern method 
of using serial sections does not seem to have been employed ; further, 
Botrychium virginianum , which affords the key to the situation, has 
strangely enough been overlooked from this point of view. 
