PLATE XXVIII. 



AsTR.?508PONGiA Hamiltonensis (page 197). 



Figure 1. A spicule from the^Hay^ River, supposed to be referable to this 



species. 

 Figure la. The same, fourteen times the natural size. 



Arachnocrinus Canadensis (page 208). 

 Figure 2. Lateral view of the dorsal cup of the only known specimen of this 



species. Twice the natural size- 

 Figure 2(f. Diagram of the plates of tlie dorsal cup of the same. I'^our times 



the natural size. 



Spirorbis omphalodes (page 209). 



Figure 3. A small and probably immature specimen, as seen from above, 

 with the outer volution rounded and someAvhat depressed, and 

 the umbilicus comparatively witle. Twelve times the natural 

 size. 



Figure 4. Similar view of a larger and probably adult example. The outer 

 volution is elevated and subangulated, and the umbilicus rather 

 narrow. Six times the natural size. 



Figure 4a. Outline of the game, as viewed laterally. 



Figure 5. Another specimen, in whicti the umbilical margin only is minutely 

 plicated, as seen from above. Four times the natural size. 



Figure 5a. Lateral outline of the same. 



CoRNULiTES (Ortonia) snBL.95Vis (page 210). 



Figure 6. A calcareous tube of this species, as seen from above, with the out- 

 line of its aperture. Both three times the natural size. 

 Figure 7. Another tube of this species, also three times the natural size. 



Hederella Canadensis (page 210). 



Figure 8. A colony of this species, as seen from above- 

 Figure 8a. A portion of the same, three times the natural size. 



Peoboscina laxa (page 212). 



Figure 9. The only specimen collected, as seen from above. 

 Figure 9a. A portion of the same, eight times the natural size. 



Stomatopora moniliformis (page 212). 



Figure 10. A colony of this species, as seen from above, and ten times the 

 natural size. 



