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The material studied by the author belongs to the Geological Survey of Canada (Calgary, Alberta), and it was entrusted to him for description after the congress in Montreal in 1972. It is not large but surprisingly multiform, dominated with specimens, whiCh in one way or other resemble true Lycopsids, and with those the study of the material started. These specimens have alI of them more or less distinct rhombs arranged in quincunx, a pattern that seems to have been considered an infalIible indicator of Lycopsids. But when the first specimen was closely exarnined no fu rthe r lycopsidean characters could be discovered. The only openings within the rhombs were single ones situated near the upper comer of each rhomb, and around these openings a thin f11m of coal with a striation of rows of very smalI cells comes up, and they are stuffed with crystals of calcite. Where an opening is damaged, part of a tube leading inwards from it is exposed (Fig. 10). By and by more extensive portions of tubes were discovered at spots where the surface of the specimen was damaged, and a reconstitution could be made of a system with main, straight tubes, width c.l mm, running through the entire length of the specimen, and diagonal secondary tubes, strongly winding, raising the covering epithelium so that ridges delirniting the rhombs were formed (schematized in the stripe above the measurement (in Fig. 8). Gradually fmer tubes were formed through branching, the fmest ones capillaries, 100 to the rnillimetre or even more across. Such fine tubes also had walIs composed of minute cells, and they were in the interior of the plant so densell packed that a coal resembling anthracite was formed (Figs. 4 & 5).

Pseudolycopsids from the rocky mountains of Canada