PLATE X. 



Zaphrentis mirabilis, Billings (page 126). 



Figure 1. Side view of the type specimen ; one-third the natural size. 

 Figure la. Longitudinal section of the same showing the depth of the calyx. 

 Figure 16. Transverse section of the same. 



Amplbxus cingulatus, Billings (page 129). 



Figure 2. Side view of one of the oorallites of a small colony from Anse h la Barbe, Que. 

 Figure 3. Longitudinal section of a oorallite from the same specimen. 

 Figure 3a. Transverse section of the same corallite. 



Pycnostylus Guelphensis, Whiteaves (page 132). 



Figure 4. Longitudinal section of a corallite to show the manner of budding ; twice 



the natural size. 

 Figure 4a. Transverse section of the same to show the triangular shape of the new 



corallites and the disposition of their septa ; twice the natural size. 



Oyathophyllum Anticostiense, Billings (page 134). 



Figure .5. Side view of a specimen from the Island of Anticosti ; one-half the natural 

 size. 



Figure 6. Longitudinal section of the upper part of another specimen from the same 

 locality, showing the calyx. 



Figure 6a. Transverse section of the same. 



Figure 7. Tangential section, near the surface, showing the dissepiments and the poorly 

 developed distal ends of the septa ; from a specimen from South- 

 west Point, Anticosti. Twice the natural size. 



Figure 8. Surface of a decorticated specimen (the type of C. solitarivm) from Portage 

 Bay, Lake Manitou, Grand Manitoulin Island, Lake Huron. Twice 

 the natural size. 



Oyathophyllum articulatum, Wahlenberg (page 135). 



Figure 9. A few corallites of a specimen from Lake Temiscaming, Que. 

 Figure 9a. Longitudinal section of a corallite. 

 Figure 95 . Transverse section of the same. 



