NUCULANA. 7 



Affinities. — This species is much smaller and less inequilateral than N. sca- 

 phoides (Piotet and Campiche). For its relations to N. scapha (d'Orbigny), 

 N. lineata (Sowerby), and N. angulata (Sowerby), see pp. 4, 7, 8. 



Types. — I have not seen the type. The specimens figured by Gardner are in 

 the British Museum. 



Distribution. — Lower Gault (zones ii, and iv to vii) of Folkestone. Gardner 

 records it also from the Folkestone Beds and the Upper Gault. 



Nuculana lineata {Sowerby), 1836. Plate I, figs. 28 a, b, 29, 30, 31 a— J, 32 a—c. 



1836. Nucula lineata, J. tie C. Sowerbi/. Trans. Geol. Soc, ser. 2, vol. iv, 



p. 342, pi. xvii, fig. 9. 

 1850. Leda lineata, A. d'Orbigny. Prodr. de Pal., vol. ii, p. 159. 

 1854. Ntjcula lineata, J. Morris. Cat. Brit. Foss., ed. 2, p. 217. 

 1S68. Leda ltneata, A. Briart and F. L. Cornet. Descript. Mineralog., Geol., 

 et Pal. de la Meule de Bracquegnies (Mem. 

 Cour. et Mem. des Saw etrangers, vol. xxxiv), 

 p. 63, pi. vi, figs. 8, 9. 

 1884. — — J. S. Gardner. Quart. Journ. Geol. Soc, vol. xl, p. 136, 



pi. iv, figs. 13-16 (?14). 

 1884. — scapha, Gardner. Ibid., p. 138 (partim), pi. v, figs. 21, 22 ? 

 Non 1837. Nucula lineata, A. Goldfuss. Petref. Germ., vol. ii, p. 153, pi. cxxiv, 



fig. 17 (from the St. Cassian Beds). 



— 1841. — — G. Minister. Petrefactenkunde, pt. iv, p. 83, pl.viii, fig. 9. 



— 1S75. Leda lineata, J. F. Blake. Quart. Journ. Geol. Soc, vol. xxxi, p. 228, 



pi. xii, fig. 12 (from the Kimmeridgian) ; 

 vol. xxxvi (18S0), p. 235. 



Description. — Shell small, oval, elongate, somewhat compressed, rounded 

 anteriorly, pointed posteriorly ; posterior part a little longer than the anterior. 

 Ventral margin slightly curved. Umboncs not very prominent. Lunule often 

 indistinct. Escutcheon lanceolate. Surface ornamented with well-marked con- 

 centric ribs, which disappear or become indistinct near the postero-dorsal and 

 antero-dorsal extremities : some of the ribs cut the ventral margin obliquely near 

 its posterior end. Margins smooth. 1 Teeth numerous, slightly bent. 



Measurements : 



(i) (2) (3) 



Length . . 12 . . 10 . .8 mm. 



Height . . 7 . 6 . . 4*5 „ 



Thickness . — . . — . . 3 ,, 



Affinities. — In this species the ribs are coarser and fewer, and the posterior 

 part of the shell is less sharply pointed and less compressed, than in N. Marias 



1 Gardner says " the lip is strongly creuated internally." I have seen no indication of this in 

 any specimen. 



