BRACHYTREMA. 99 
p. 5, pl. 44, fig. 27), approaches our shell still more closely, but the spiral ornamen- 
tation of Lycett’s species is finer, more crowded, and more granulated. It is 
true that in all these cases the differences are chiefly connected with the ornamen- 
tation, and in this respect B. subvaricoswm certainly differs from all known forms 
of Brachytrema in the Great Oolite of this country. It is possible that this may 
be the form described by Cossmann (p. 79, pl. xi, figs. 34 and 35) as Brachytrema 
brevis, Piette, said to be not uncommon in the Bajocian of the Meurthe-et-Moselle. 
Brachytrema subvaricosum occurs sparingly in the upper part of the Lincolnshire 
Limestone at Great Ponton. There is also a wide-angled variety, with the spirals 
very wide apart, which has been found at Weldon. 
18. BrachytremA BINODOsUM, sp. nov. PI. VII, fig. 12. 
Description.—This little shell differs from all others of the varicoswm-group in 
having two nodular spiral belts round the whorls, which give it an eucycloid aspect. 
A single specimen has been found at Great Ponton. 
19, Bracnyrrema Waricutil, Cotteau, 1855, var. pespecta. Plate II, figs. 8 a, 0, ¢. 
1860. BracuyrremMa Wriaurtit, Cotteau. Héb. and Desl., Foss. de Montreuil- 
Bellay, p. 21, pl. vii, figs. 7 a, 8, e. 
Description : 
Length . : : : . 75 mm, 
Width : ; . 6mm. 
Body-whorl to entire hell Ange : . a0 5100 
Spiral angle : : 65° 
Shell conical; apex pointed. Whorls five, angular, and Soe -like ; ornaments 
coarse ; three strong nodulated spirals on the anterior area of each whorl; the 
longitudinals consist of tolerably numerous stout costa which are very nodular 
over the angle of the whorl ; base rather flattened and ornamented by five spiral 
lines. 
Aperture subquadrate to circular; notch rather wide ; scarcely any canal. 
Relations and Distribution.—Owing to the indifferent preservation of the 
anterior margin of the only known specimen it is not easy fully to point out how 
the form now under consideration differs from Cotteau’s species. It is not much 
