SPORE-PRODUCING MEMBERS 321 
details in them restricts the comparison to the basis of mature structure. 
On this footing it appears that the type of sporangium characteristic of 
the sub-genus Uvostachya, and showing special resemblance to that of 
Lycopodium Phlegmaria, dates back at least to the calciferous sandstone, 
for it is seen in Lycopodites Stockit (compare Fig. 147). Sporangia apparently 
of the same type have been recognised also in other early fossils referred 
to Lycopodites, but their small size and the state of preservation do not 
We 
el 
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Fic. 167. 
Spencerites insignis. Somewhat diagrammatic radial section of part of the cone, 
showing two sporophylls in connection with the axis. On the lower sporophyll the 
sporangium is shown attached at its distal end to the ventral outgrowth of the sporophyll : 
within the sporangium some of the characteristic winged spores are shown. (After Miss 
Berridge.) From Scott, Progressus rei Botanicae, vol. i. 
allow of any exact comparison. Of other apparently non-ligulate types one 
of the best known as regards the details of the strobilus, though its vegetative 
region is still unknown, is Spemcerites (Fig. 167), which has been described 
by Scott and others from specimens showing microscopic structure. Here 
the verticillate or spiral sporophylls consist of a narrow pedicel bearing an 
upturned lamina; at the base of the lamina is a massive ventral outgrowth, 
to which the distal end of the sporangium is attached by a narrow neck. 
The presence of the ventral sporangiferous lobe has suggested to Dr. Scott 
a comparison with the Sphenophyllales, though the absence of any vascular 
supply to the “ventral lobe” renders the analogy somewhat remote. It 
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