1908] JEFFREY—FOLIAR GAPS . 255 
tion is figured in the cones of the remarkable genus Cingularia. Our 
information on the subject of the strobilus of the important calamitean 
genus Palaeostachya has recently been materially increased by the 
important investigations of Hicki1NG.'5 This author states: “From 
an examination of the numerous sections cut more or less transversely 
through the node, I feel little doubt that no regular pectination 
occurred; while on the other hand one or two sections showed 
features which seemed explicable only on the assumption that an 
occasional communication (probably irregular) did occur between 
adjacent bundles.” The conditions in this genus of calamitean cone 
would seem accordingly to have approximated very, closely those 
existing in the strobilus of the modern Equisetum, so far as the course 
of the bundles in relation to the nodes was concerned. This resem- 
blance is all the more striking because, lower down on the same page, 
the author states that the sporophyll trace left the axial strand with- 
out giving rise to any foliar gap. His words are “no gap ts left in the 
main bundle.” The italics are those of the present writer. “The main 
bundle” here means the bundle of the axis from which the sporophyll 
trace was derived. It will be readily inferred from the various 
Citations given above that, in spite of the conviction expressed by 
Dr. Scorr that foliar gaps occurred in the vegetative stem of the 
Calamites, they must have been generally absent in the cones of the 
more important calamitean types. There seems accordingly little rea- 
son to doubt, when the foliar relations of the more modern Calamites 
are fully worked out, since the course of their internodal strands resem- 
bled that found in Equisetum, that they will prove to be very similar 
to those of the living genus; and, in view of the similarity shown above 
in the fibrovascular arrangements of the cone, will be susceptible of 
a similar interpretation. This follows all the more certainly because 
$0 distinguished an authority as Dr. Scorr himself states, in his 
Studies in fossil botany: “Thus the calamite, so far as anatomy goes, 
‘S simply an Equisetum with secondary thickening.” 
The conditions in Archeocalamites, the oldest calamitean genus, 
= particularly significant. In this form one of the most character- 
Stic features was the failure of the primary fibrovascular strands of 
the Vegetative stem to alternate at the nodes, as they do in the more 
‘s Anatomy of Palaeostachya vera. Annals of Botany 21:375- 1998. 
