BRACHIOPODA. 



365 



rig. 151. Terehratella. 



fathoms. Fossil, 90 species. Carb — . SoutL. America, Europe. 

 Eudesia (cardium), King, includes 1 recent a^d 6 fossil species 

 which are sharply plaited. T. impressa (PI. XY., Fig. 5) is 

 the type of a group which has the external shape of Terehratella. 

 Meganteris, Suess, 1856. Terebratula Archiaci, Yern. Devo- 

 nian, Asturias. Shell with a long, reflected, internal loop. 



Terebeatella, D'Orbigny. 



Type, T. dorsata, Gmel. (= Magel- 

 lanica, Chemn.) PL XY., Fig. 7. Fig. lol. 



Shell smooth or radiately plaited ; dorsal 

 valve longitudinally impressed ; hinge- 

 line straight, or not much curved; beak 

 with a flattened area on each side of the 

 deltidium ; foramen large ; deltidium in- 

 complete ; loop attached to the septum (s). 



Animal like Terebratula ; the spiral lobe 

 of the brachial disk becomes very 

 diminutive in some species, and is 

 obselete in Morrisia and T. Cumingii. 

 Distribution, excluding sub-geiiera, 

 25 species. Cape Horn, Yalparaiso 

 (90 fathoms), New Zealand, Japan, 

 Ochotsk, Spitzbergen, Labrado*r. 

 Fossil, 16 species. Lias—. United ^ig- 152. Ter. Evansii, Dav. 

 States, Europe. In T. crenulata and Evansii (Fig. 152) the 

 dorsal septum sometimes projects so far as to touch the oppo- 

 site valve, but in other examples it remains undeveloped. 

 (Davidson.) 



Sub-genera. Trigonosemus (elegans), Konig. Synonyms, Del- 

 thyridsea (pectiniformis), M'Coy. Fissirostra, D'Orbigny. 

 Example, T. Palissii, PL XY., Fig. 8. Shell finely plaited, 

 beak prominent, curved, with a narrow apical foramen ; cardinal 

 area large, triangular ; deltidium solid, flat ; cardinal process 

 very prominent. Distribution, 5 species. Chalk, Europe. 



Lyra (Meadi), Cumberland, Min. Con. 1816. PL XY.,Fig. 6. 

 Synonyms, Terebrirostra, D'Orbigny. Ehynchora, Dalman.* 



* The name Rhynchora was given by Dalman to the Ter. costata. Wahl, = T. 

 pectinata, L.) on the supposition that it was identical with Sowerby's T.Lyra; and 

 aa no specimen could be found with a long beak, an artificial one was manufactured 

 for it, of which there is a cast in the British Museum. The second species of " Ehyn- 

 chora," Ter. spatulaia, Wahl., has no beak whatever: in shape it is like an Argiope, 

 but measures an inch each way. The ventral valve is a simple bent plate with the 

 teeth at the angles ; the dorsal valve is flat, with a very wide hinge-plate, and sockets 

 at the angles, whilst a single septum projects from the centre, with portions of a lotij* 

 attached. 



