PLATE XXIX. 



AtTLOPORA FiLiPORMis, Billings, (page 211). 

 Figure 1. Side view of the only known specimen of tliis species, which has 

 not previously been figured. Introduced for comparison- 



Chonetes Logani, var. Aurora (page 215). 



Figure 2. Ventral valve of a specimen from the Mackenzie River at the 

 " Ramparts." 



Figure '2a- Portion of the same, magnified four times, to shew the surface or- 

 namentation. 



Productella spinulicosta (page 217). 

 Figure 3. Dorsal view of a specimen from the Hay River, which is somewhat 



doubtfully referred to this species. Twice the natural size. 

 Figure Zn. Profile view of the same, also twice the natural size. 



Figure 4. 



Spirifera dis.juncta (page 221). 

 Dorsal view of a perfect and typical specimen from the Hay River. 



Spirib'era dis.iuncta, var. ocoidentalis (page 222). 



Figure 5. Dorsal view of a specimen from the Hay River. 

 Figure 5a. Profile view of the same. 



Batonia variabilis (page 233). 



Figure 6. Dorsal view of a specimen with the front margin subtruncated, 



and four plications on the dorsal valve. 

 Figure 6a. Profile view of the same. 

 Figure 7. Dorsal view of a specimen in which as many as thirteen plications 



can be counted on the regularly rounded front margin. 

 Figure 8. Dorsal view of a specimen in which there are only two central and 



no lateral plications in the dorsal, and in which the front 



margin of both valves is produced into a short rounded lobe. 

 Figure 8a. Profile view of the same- 

 Figure 9. Portion of the umbonal region of another specimen, to show the 



perforate beak of the ventral valve. 



Stringooephalus Burtini (page 235). 



Figure 10. Outline of the dorsal aspect of a cast of the interior of both valves 

 of this species, of normal form. 



Figure 10a. Outline of the same, in profile. 



Figure 11. Dorsal view of another cast of the interior of a shell of this species, 

 of unusually globose form, and in which the beak of the ven- 

 tral valve is strongly recurved over that of the dorsal. 



Figure 11a. Profile view of the same. 



