250 MESSRS. G. W. LAMPLUGH AND J. F. WALKER ON [May I9O3, 



divided this species into minute varieties, which he distinguished 

 by the letters a and b. We have found many other varieties which 

 were not figured by him : if we compare the large wide forms with 

 the more ovoid convex specimens, we find marked differences ; but 

 with the abundant material that we possess, we are able to connect 

 together every variation of this species. Terebratula capillata is 

 the characteristic fossil of the Shenley Bed : it occurs both in the 

 calcareous and in the ferruginous part of the deposit, and also in 

 the pink limestone. 



The geographical range of T. capillata is very great. It has been 

 found in the Tourtia of France, Belgium, also in Westphalia and 

 near Dresden in Germany, and in Southern India. In England it 

 occurs in the Eed Chalk of Norfolk, Lincolnshire, and Yorkshire, 

 and in the Aptian of Upware. 



Measurements op Terebratula capillata (in millimetres). 



Apical 



Length. Breadth. Thickness, angle. 



A large, wide, flat specimen 35-0 33'5 16-50 100° 



Specimen with wide fold 27'0 23*5 12'00 95° 



Smaller specimen with wide fold... 19'5 17*5 8'50 91-5° 



An ovoid globose specimen 21*0 18'5 12\50 92° 



Young specimen 135 120 5'75 88° 



Very young specimen 7*25 66 3'50 87'3° 



A specimen of T. capillata from the Eed Chalk of North Grimston 

 (Yorkshire) yields the following measurements : length = 23*75 

 millimetres ; breadth = 21 mm. ; thickness = 14*25 mm. ; and 

 apical angle = 90°. 



Terebratula biplicata, Sow., var. gigantea, nobis. (PI. XVI, 

 figs. 7 rt-7 c.) 



1812. Terebratula biplicata, J. Sowerby, ' Mineral Conch.' vol. i, p. 201 & pi. xc. 

 1825. Terebratula biplicata, Sow. ibid. vol. v, p. 53 & pi. ccccxxxvii, figs. 2-3. 

 1847. Terebratula Dutempleana, A. d'Orbigny, 'Pal. Franc. Terr. Cret.' vol. iv, 



p. 93 & pi. dxi, figs. 1-8. 

 1852. Terebratula obesa, Davidson, 'Brit. Cret. Brachiop.' Monogr. Pal. Soc. 



p. 53 & pi. v, figs. 13-16. # 



1854. Terebratula biplicata, Davidson, op. cit. p. 55 & pi. vi, figs. 1-42. 

 1868. Terebratula biplicata, Scbloenbach, in Benecke's Geogn.-Pala.ont. Beitrage, 



vol. i, p. 433 & pi. xxi, figs. 1-3 & 6. 



1871. Terebratula biplicata, Quenstedt, ' Brachiop.' p. 381 & pi. xlviii, figs. 61-67. 



1872. Terebratula biplicata, Geinitz, ' Elbthalgebirge ' p. 151 & pi. xxxiv, figs. 1-6. 

 1872. Terebratula biplicata, var. Dutempleana, Stoliczka, Pal. Indica, 'Cret. 



Fauna S. India ' vol. iv, p. 20 & pi. v, figs. 1-3. 

 1874. Terebratula biplicata, Davidson, ' Brit. Cret. Brachiop.' Suppl. Monogr. 



Pal. Soc. p. 33 & pi. v, figs. 1-2. 

 1878. Terebratula biplicata, Deicke, ' Die Brachiop. der Tourtia von Mulheim ' 



p. 10 & (pi.) fig. 1. 

 1900. Terebratula biplicata, Jukes-Browne, ' Gault & Upper Greensand of 



England ' Mem. Geol. Surv. p. 58, fig. 24. 



The large biplicated form which has been considered a giant 

 variety of Terebratula biplicata, Sow. occurs in this bed. Davidson 

 regarded it as a variety of T. obesa, but in his Supplement referred 

 it to T. biplicata. For convenience, and to prevent confusion, we 

 have given these specimens a varietal name, gigantea. The 

 biggest specimen measures : in length, 74 millimetres ; in breadth, 

 48 mm. ; its greatest thickness =38 mm. ; and its apical angle =43° 



