MancJiester Memoirs, Vol. I. (1906), No. 10. 3 



becomes much less perfect, and the number of the petioles 

 less, till finally in the last few sections the tissues of the 

 main axis and neighbouring petioles appear to be extremely 

 immature, and must lie near the growing point. 



The general structure and appearance of the plant is 

 that of a herbaceous fern. The distinctive character of 

 the numerous petioles, which come off from the main 

 axis as small branches and increase in size as they leave 

 it, is only found in ferns that live in the ground. The 

 general arrangement is like that of an Aspidiiim or 

 Athyrium among living ferns, or an Osmtindites among 

 fossils. The rapid increase in size on the part of the 

 petioles till they greatly exceed the main axis in diameter 

 separates it further from most ferns, though this is also 

 characteristic of some species oi Athyrium. The form of 

 the meristele, however, differs from any of these, as its 

 simple horseshoe curve is orientated with the convex side 

 toward the main axis, a feature of great rarity, which 

 occurs only in Asterochlaena dulbia, possibly in Anacho- 

 ropteris, and in Tubicaulis Solenites. 



The petioles apparently come off from the axis 

 equally on all sides, and bend slowly away from it. The 

 main axis itself appears to have been nearly vertical, but 

 to have bent slightly. Large numbers of roots coming 

 off from the axis and petioles branch there, and run in a 

 most irregular fashion. One is led to believe that the 

 plant was probably growing underground, the main axis 

 being a nearly vertically running rhizome. The enormous 

 number and the size of the petioles in comparison with that 

 of the stem indicate that in the air the axis could not 

 well have been self supporting, while their close arrange- 

 ment and very short internodes preclude the idea of a 

 climbing plant. The leaf bases apparently persisted for 

 a long time, as there are many in the lowest section 



