246 



DEVELOPMENT OF FAMILIES, ETC., IN TIME. 





Recent. 



Fossil. 





Recent. 



Fossil. 



Nucleubranchiata. 





CONCHIPERA. 







FirolidfiR, . . 



. 33 



1 



Ostreidee, . . 



426 



1362 



Atlantidse, 



. 22 



159 



Aviculidse, 



94 



638 









Mytilidpe, . . 



2n 



331 





55 



160 



Arcadse, . . 



360 



1142 









Trigoniadae, . 



3 



139 



Pteropoda. 







IJnionidse, . . 



. 549 



58 



Hyaleidse, . . 



. 52 



95 



Chamidas, . . 



. 50 



62 



Limacinidge, . 



. 19 



— 



Hippuritidge, . 



— 



103 



Clionidse, . . 



. 14 



— 



Tridacnidse, . 



8 



3 









Cardiadffi, . . 



. 200 



360 





85 



95 



Lucinid^, . . 



. 178 



446 









Cycladida\ 



. 176 



144 



Brachiopoda. 







Cyprinidse, 



. 176 



956 



Terebratulidse, 



. 67 



340 



Yeneridae, . . 



. 600 



329 



Spiriferidse, . 



— 



380 



Mactridge, . . 



. 147 



58 



RhynchonellidiB, 



4 



422 



Tellinidse, . . 



. 560 



388 



OrtMdse, . . 



— 



328 



Solenida3, . . 



. 63 



81 



Productidse, . 



— 



146 



Myacidse, . . 



. 121 



334 



Craniadffi, . . 



5 



31 



Anatinidje, 



. 246 



400 



Discinidse, . . 



. 10 



90 



Gastrochseiiidse , 



. 40 



35 



Lingulidae, 



. 16 



99 



Pholadidae, 



. 81 



50 





102 



1842 





4295 



7419 





General 



Summary. 









Recent. 



Fossil. 





Recent. 



Fossil. 



Dibranchiata, . . 



204 



189 



Nudibranchiata, . 



318 







Tetrabranchiata, . 



6 



2193 



Nucleobranchiata, 



55 



160 



Prosobranchiata, . 



8465 



5819 



Pteropoda, . . . 



85 



95 



Inoperculated Pul- 







Brachiopoda, . . 



102 



1842 



monifera, . . . 



5404 



542 



Conchifera, . . . 



4295 



7419 



Operculated Pul- 







^ 











monifera, . . . 



931 



46 



2 



0,502 



18,568 



Tectibranchiata, . 



356 



263 









