MOLLUSCA. 



CLASS III. BRACHIOPODA. 



ORDER I. INARTICULATA. 



Fam. a. Lingulidse. Lingula. 

 Fam. b. Discinidse. Discina. 

 Fam. c. Craniadse. Crania. 

 Fam. d. *Trimerellidse. Trimerella. 



ORDER II. ARTICULATA. 



Fam. a. Terebratulidse. Terebratula, Argiope. 



Fam. b. Thecidiidse. Thecidium. 



Fam. c. *Spiriferidse. 'Spirifera, Athyris. 



Fam. d. *Koninckinidse. Koninckina. 



Fam. e. Rhynchonellidse. Rhynchonella. 



Fam. /. *Pentameridse. Pentamerus. 



Fam. g. *Strophomenid8e. Strophomena, Orthis. 



Fam. h. *Productidse. Producta. 



(Owen, Anatomy of the Brachiopoda, Trans. Zool. Soc., 1835 ; Hancock, 

 On the Organisation of the Brachiopoda, Phil. Trans., 1858 ; Davidson, 

 Monograph of the British Fossil Brachiopoda, Palaeontographical Soc., 

 1851-81.) 



Pig. 72. Morphology of Srachiopoda. A, Lingula pyramidata (after Morse) : p, Peduncle ; 

 *, Sand-tube, encasing base of peduncle. B, Lingula anatina (after Cuvier) : p, The peduncle, 

 c, Waldheimia cranium, with adherent young, attached to a stone (after Davidson) : p, Pe- 

 duncle ; v, Ventral valve ; d, Dorsal valve. D, Crania Ignabergensis, attached by its ventral 

 valve to a piece of coral (Chalk). 



