310 
AMERICAN JOURNAL OF BOTANY 
[Vol. 8 
The writer^^ examined with great care the development of the fibro- 
vascular system in the young sporophytes of Danaea Jamaicensis Underw. 
and D. elliptica Smith, and also the younger stages of the sporophytes 
of species of Angiopteris, Kaulfussia, and Marattia. In all of these (fig. 5, A) 
it was found that the primary root is deep-seated, growing through the 
foot precisely as it does in Ophioglossum Moluccanum and Botrychium 
obliquum, and there is a single primary stele traversing the axis of the 
cotyledon and root (fig. 5, 5). The young plant is thus bipolar, so far as 
the cotyledon and root are concerned, and the insignificant stem apex 
appears as a small lateral appendage near the junction of the two primary 
organs. No procambium can be made out in the very small mass of tissue 
which can be assigned to the stem. 
This is particularly well shown in Danaea (fig. 6), where the stem apex is 
seen in the angle formed by the junction of the bundle from the second leaf 
with the primary bundle, but no sign of procambial tissue can be seen in 
the region above this junction. 
7" 
A 
Fig. 6. A. Longitudinal section of young sporophyte of Danaea elliptica, showing the 
junction of the two leaf-traces. B. The stem apex of the same sporophyte with the trace 
of the second leaf, l^, passing to one side of it. 
21 Campbell. The Eusporangiatae. 
