NOTES ON THE BRITISH JURASSIC BRACHIOPODA. 233 



Terebratula proper is first met with in the Jurassic rocks, 

 but was represented in the Devonian, Carboniferous and 

 Permian, by a near ally, Dielasma. It is represented in 

 existing seas by another close ally, Liothyrina, of which 

 eight to ten species are known. 



Excluding three unnamed shells, Davidson figured and 

 described in his Jurassic Monograph fifty- three species, three 

 doubtful species, and fifteen varieties of Terebratula from the 

 Lias and Oolites of this country. The following species, all 

 of which belong to other genera, nanst, however, be deducted 

 from that number : — Ter. (?) fiahellum, hemisphserica, perieri, 

 suessi, hybrida, iiiorierei^ coarctata, and var. reticulata, bentleyi, 

 curviconcha, curvifrons, galeiformis, provincialis, bolo?iiensis, 

 and gesneri. 



It is interesting to note that only four species and three 

 varieties are recorded for the Lias, while of the remainder 

 no less than twenty-seven species and nine varieties are from 

 the Inferior Oolite. 



Very few additional species have been made since David- 

 son's death. The following are the only ones that have 

 come under my notice : — ^ 



Ter. pisolithica, S.S.B., Inferior Oolites of the Cotteswolds (2). 

 ,, notgroviensis, S.S.B., „ ,, ,, ,, ,, (2). 



,, euides, S.S.B., ,, „ „ Dorset.^ 



„ decipiens, var. chadivicJci, W. and B., Dogger of the Peak, 

 Yorkshire (18). 



Mr. Walker has also identified the two following species : 

 Ter, repeliniana, d'Orb., found by Mr. S. Chadwick in the 

 Coral-rag of Helmsley, Yorkshire (18), and Ter. ovatissima^ 

 Quenst., found in the Lower Lias of Radstock. There existy 



* Vide Appendix. 



2 Geol. Mag., Dec. HI., Vol. III. (1886), p. 218. 



B 



