Vol. 6, 1920 
BOTANY: D. H. CAMPBELL 
503 
Danaea also develops a suspensor. The relative positions of the first 
leaf and primary root, also recall the embryo of some species of Ophio- 
glossum. 
As in Danaea and Ophioglossum, the young sporophyte of B. obliqmtm 
is bipolar in structure, the primary leaf or cotyledon and the primary 
root having a common axis traversed by a single vascular bundle which 
is continued from one into the other. The root is endogenous in origin, 
and pushes its way vertically downward, penetrating the foot which is 
practically destroyed. The stem apex is very inconspicuous, and is 
situated between the cotyledon and the primary root. No stelar tissue 
is developed from the stem-apex, and the vascular system of the young 
sporophyte is made up exclusively of a union of vascular strands belonging 
to the leaves and roots. 
The primary leaf is ternate in outline, and closely resembles the first 
foliage leaf of Helminthostachys. 
The embryo of B. obliquum differs from that of B. lunaria in several 
important particulars. The embryo of the latter is in its early stages 
composed almost entirely of the foot and root between which is the very 
inconspicuous stem-apex. The early leaves are reduced to mere scales, 
and it is several years before the first green leaf is formed. 
B. Virginianum, on the other hand, has the primary leaf even better 
developed than it is in B. obliquum, but the root is of external origin, 
the very large foot is persistent, and the cotyledon makes a sharp angle 
with the root. 
B. obliquum agrees with Helminthostachys in the development of a 
suspensor, but the position of the organs of the embryo in the latter is 
more like B. Virginianum. In Helminthostachys, also, the first leaf is 
rudimentary. The second leaf is functional and closely resembles that 
of B. obliquum. 
It looks as if B. obliquum were more generalized than the other species, 
suggesting a relationship on one hand with Ophioglossum, on the other 
approaching Helminthostachys, as well as the Marattiaceae, especially 
Danaea. 
The differences in the embryos of the three investigated species of 
Botrychium, are accompanied by significant differences in the adult 
sporophytes, probably sufficient, together, to warrant a separation of 
the genus into three genera. 
The *'Ternatum" division of the genus Botrychium to which B. obliquum 
belongs, would probably constitute the genus Sceptridium, Lyon; Blunaria, 
the type species, and its allies, would retain the generic name Botrychium 
Sw., while B. Virginianum would be the type of Osmundopteris, Milde. 
1 A New Genus of Ophiolglossaceae, Bot. Gaz., Chicago, 40, 1905 (455). 
