1908] JEFFREY—FOLIAR GAPS 245 
ing in a Sigillaria with separate fibrovascular strands. In the cone 
of Phylloglossum individual sections often present an appearance still 
more misleading. In fig. ro is shown such a condition. A horse- 
shoe-shaped fibrovascular mass appears in the center, and oppo- 
site its opening a sporophyll trace. To the right and left below 
are two other foliar traces. An inexperienced anatomist might readily 
conclude that the gap opposite the uppermost trace was a true foliar 
gap. Fig. rz shows a section from another cone, with two such 
apparent foliar gaps, one on each side, each apparently subtended 
by its corresponding leaf-trace. Fig. 12 shows another section from 
the same cone, a small fraction of a millimeter lower down. It is 
here to be noted that the foliar trace on the right in the preceding 
figure joins the face of the large cauline fibrovascular strand, forming 
the same radially elongated mass as is characteristic of the outgoing 
Sporophyll traces shown in fig. 8 from the peduncle. Still lower 
down, as was learned from the study of serial sections, the foliar 
strand on the left joined the outside of its cauline strand in a similar 
manner. A study of the cone of Phylloglossum has shown that the 
traces for the sporophylls invariably pass off from the outer surface 
of the central cylinder without leaving any real foliar gaps. Some- 
limes two or even three traces may originate along the margins 
of the same hiatus in the stele. The interruptions in the central 
cylinder or stele are no more to be regarded as foliar gaps than are 
the corresponding ones in certain Sigillarias. It is obviously impos- 
sible with any clear eye to anatomical relations to regard the perfo- 
rations which exist in the upper part of the fibrovascular system of 
the stem in Phylloglossum as being of the nature of foliar gaps. 
Miss SYKEs has recently reached the conclusion that the living Lyco- 
Podiaceae originated in all probability by reduction from the more 
complex arboreous lycopods of the Paleozoic period.s Without pre- 
suming to indorse this view, it may be pointed out that it stands in 
way of presumably reduced modern lycopodineous forms in any 
“ase possessing the foliar gaps which were denied to their sup- 
ea Paleozoic ancestors, which possessed very much larger 
Ves, 
er of the sporangium-bearing organs in the Lycopodiaceae. New 
logist 7241-60, 1908, : 
