380 West. — A Contribution to the Study of the Marattiaceae. 
from the ends of the large terminal strand (Text-fig. 12, vii-xii, c.s.) assist 
in repairing the gaps made in the petiolar curve by the departure from its 
flanks of strands 1, 3, 5 and 2, 4, 6 respectively, and their function is 
therefore strictly analogous to that of the compensating (= Ersatz ) strands 
in the stem-stele. Finally, the terminal strand divides into two, the 
Text-fig. 12. i-xii. Danaea alata , Sm. The figures illustrate in suc^' ssive, but not consecutive, 
transverse sections the changes and rearrangements that occur in the vascular strands of the rachis, 
including the region of the lowermost pinnae. The position of the protoxylem groups is denoted by 
the black areas, c.s., compensating strand, x 6. For description see text. 
respective halves fusing with the two adaxial strands of the curve, as shown 
in Text-fig. 12, x-xii. The petiolar curve at a level immediately above the 
point of insertion of the lowermost pair of pinnae is represented in Text- 
fig. 12, xii. 
Case II. In the second case the arrangement of the petiolar strands 
at a level immediately below the point of insertion of the lowermost leaf- 
