143 
Decouvertes de quelques Testacees Petrifies rares et inconnus, pour 
servir a V Histoire Naturelle de la Basse Allemagne, Pl. iv. This 
fossil was figured by Langius, Hist. Lap. Fig. Helv. PI. 21, Fig. 4; 
and the figure of Langius has been copied by Bourguet, TraiU des 
Petrijications, Fig. 316. 
Both the specimens of this fossil, discovered by Baron de Hupsch 
and by Faujus St. Fond, are merely casts of the chambers of the shell, 
Spondylolithes ; and such also is the specimen which I have also had 
the good fortune to obtain from Maestricht, and which is represented 
Plate IX. Fig. 2. This fossil, it may be observed, approaches nearer 
in size to that of Langius, than to that figured in Faujus St. Fond’s 
elegant work. I must here remark, that the absence of a siphuncle, 
assumed by Lamarck, cannot be proved from the mere casts of the 
chambers, which is the only state in which we have yet seen this fossil. 
It is about five years since I first met with the fossil represented 
Plate X. Fig. 1, with some others, at the shop of Mr. Heslop, who 
had received them from the coast, not far from Dover. Since that 
time I have been favoured, by my friend Mr. Herbert, with other spe- 
cimens, from the same coast, on some of which are remains of the 
original pearly part of the shell. From a comparison of these fossils 
with the baculites of Lamarck, it appears that the chief difference is, 
that the septa of the baculites are disposed in a straight transverse di- 
rection, whilst in these fossils they are placed in an oblique transverse 
direction. Among these fossils were some which were slightly bent 
at their smaller end, as at Plate X. Fig. 2 ; and others so much so, as 
to show that this was their natural form, and not the effect of accident. 
For fossils bearing a character so completely distinct, the necessity 
of forming a new genus seemed to be obvious, and analogy appeared 
to support the arrangement. As there is a genus ( Orthocera) of 
straight multilocular shells, with plain septa ; so there appears to be 
a corresponding genus of straight multilocular shells with sinuous 
septa, forming the genus Baculites. And as there are two more 
