PLATE 49 A. 



Page 



Fig. 1. CyPRICAEDINIA LAMELLOSA. 266 



1 a. A specimen, natural size. 

 1 b. The same enlarged to nearly tliree diameters. 

 1 c. Cardinal view of the same enlarged. 



Fig. 2. Cypkicardinia dorsata. 267 



2. The right valve of this species. 



Fig. 3. Megambonia mytiloidea. 276 



3 a. The right valve of the specimen. 



3 b. Profile view of the same. 



Fig. 4. Megambonia ovoidea. 276 



4 a. The left valve of the specimen. 



4 4. Profile of the same, looking iijjon the cardinal line; the beak of the right valve broken off. 



Fig. 5. Megambonia suborbicularis, 273 



5. A cast of the left valve of this species. 



Fig. 6. AviouLA sxjbeqtjilatera. 281 



6. The left valve of this species. 



Fig. 7. Megambonia obscura. 277 



7. The right valve of the specimen. 



Fig. 8. Megambonia aviouloidea. 274 



8. The left valve of a specimen of this species. 



Fig. 9. AvicuLA [ ? ] navipormis. 279 



9 a. A left valve preserving the entire form, with some remains of the shell, showing the 

 concentric lamellose markings and the radiating stria. 



9 c. A larger individual in which the radiating striae are scarcely shown. 



9 6. A large individual, in which the shell is better preserved than in the other specimens : 

 the umbo is proportionally less elevated, and the continuity of tlie hinge-line is interrupted 

 or obscured by the surrounding stone. The radiating stria are a little too strong in the 

 figure. 



