16 
Explanation of Plate III. 
Cryptoph ragmus antiquatus Raymond. 
Figure 1. 
“ 2 . 
“ 3, 
“ 4, 
“ 5. 
A somewhat diagonal transverse thin section, showing the central 
tube with its vesicular wall, the cross-section of three partitions, 
and the radial tubes of the outer sheath zone. Between the tube 
wall and the sheath zone is an area of calcite in which the crystals 
are coated with a brown substance, thus producing, in the photo- 
graph, an appearance of structure in the “clear zone/' Enlarged 
3 diameters, 
A specimen from near Ottawa, showing the somewhat abrupt curv- 
ature of some specimens. From the top of the Pamelia, 2 miles 
north of Aylmer, Que. Natural, size. 
Transverse section just at the top of one of the convex partitions, 
the dark circle at the centre being the top. Just what the meaning 
of the structures seen in this section may be has not been deter- 
mined. X 3. 
Tangential section of the specimen shown in Plate II, showing the 
exceedingly numerous tubes in the sheath. X 3. 
Section similar to figure 4, and from the same specimen, but not 
strictly tangential. At the centre it cuts into one of the structure- 
less zones. X 3. 
