650 
Transactions of the Society. 
This species may be recognized by the compressed outer margin 
of the test, which is strongly keeled at the commencement. This 
feature serves to distinguish it from Reuss’ C. ceplialotes* Berthelin 
gives a figure of a Cristellarian of this elongate type/j* along with 
another figure, both under the name of G. trunculata. The former 
figure is evidently a typical specimen of C. cejfhalotes ; the latter 
figure , i however, being distinct from the other forms, is here treated 
as Berthelin’s type of G. trunculata, and will be found noted subse- 
quently in this series. 
G. Bronni was described by Romer from the Hilsthon, and by 
Reuss from the “ Speeton clay ” of North Germany. 
It was found in the Folkestone Gault in zone ii., specimen h, very 
rare ; zone ii., specimen c, very rare ; zone iv., very rare ; zone v., 
very rare ; zone vii., rare ; zone x., frequent. 
Gristellaria lituola Reuss, plate IX. fig. 14 a, b. 
Gristellaria lituola Reuss, 1845, Verstein. bohm. Kreidef., pt. ii. 
p. 109, pi. xxiv. fig. 47. 
This very distinct species was found in the Planermergel of 
Bohemia by Reuss. 
In the Gault of Folkestone it was found in zone i., specimen h, 
very rare ; zone xi., 45 ft. from the top, very rare. 
Gristellaria navicula d’Orbigny, plate X. fig. 1. 
Gristellaria navicula d’Orbigny, 1840, Mem. Soc. geol. France, 
ser. i. vol. iv. p. 27, plate ii. figs. 19, 20. G. navicula Reuss, 1845, 
Verstein. bohm. Kreidef., pt. i. p. 34, plate xii. fig. 27. 
This species is a familiar one in Cretaceous faunas. It has been 
recorded from the Gault of Montcley, France (Berthelin) ; the 
Planermergel of Bohemia (Reuss) ; the Senonian-marl of Westphalia 
(Reuss) ; the Phosphatic Chalk of Taplow (Chapman) ; the Chalk of 
Sens and Meudon, France (d’Orbigny) ; the White Chalk of Kent 
(Rupert Jones in Morris’s Cat. of Br. Foss.) ; the Upper Chalk of 
the North of Ireland (Wright) ; and from the Chalk of Maestricht 
(Reuss). 
G. navicula was found in the Gault of Folkestone in zone iv., 
very rare ; zone xi., 50 ft. from the top, very rare ; 45 ft. very rare. 
Gristellaria sulcifera Reuss, plate X. fig. 2 a, h. 
Cristellaria sulcifera Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. 
Wien, vol. xlvi. pp. 74, 93, pi. viii. figs. 8 a, h. 
This species is distinguished from the allied forms of G. navicula 
and C. Italica by its grooved sutural lines. It was described by Reuss 
* Sitzungsb. d. k. Ak. Wiss. Wien, 1S62, vol. xlvi. p. 67, pi. vii. figs. 5, 6. 
t Mem. Soc. geol. France, 1880, ser. 3, vol. i. No. 5, p. 53, pi. iii. fig. 26 a, 6. 
