OWEN ON THE BELEMNITE. 119 



layers on the banks of the Olona, and contains numerous well- 

 preserved sub-apennioe species of fossil shells and large fragments 

 of semi-carbonised wood. The fossils mark the pliocene origin of 

 the strata. Besides these marine beds there is one of fresh-water 

 origin, found on the banks of the Lake of Como and consisting 

 chiefly of clay used in the manufacture of tiles and pottery, and 

 others of the same date are found in the neighbourhood. Fossils 

 are very rare throughout these strata. 



The existence of small patches of tertiary marls in these localities 

 is interesting, as marking points on the northern shores of the an- 

 cient pliocene ^sea, traces of which shores had been previously in- 

 dicated by several geologists. They prove also that the general 

 configuration of the Lake of Como was not much unlike what we 

 now see, before the last^disturbances took place, which have affected 

 some of the lacustrine marls of Villa. 



In conclusion, it is interesting to notice the general direction of 

 the successive dislocations which have produced the actual contour 

 of this district. These appear to be two in number, one of them 

 having for its mean the direction of E.S.E., the general strike of 

 the conglomerate and black limestones of the Val Sasina, of the 

 dolomitic limestones of Menaggio, and of the cretaceous beds be- 

 tween the Lago Maggiore and the Adda. The other is exhibited 

 in the oolitic formations west of the Lake of Como, and runs almost 

 constantly E. 16° N. 



D. T. A. 



V. A Description of certain Belemnites, preserved, with a great 

 Proportion of their Soft Paints, in the Oxford Clay at Christian 

 Malford, Wilts. By Richard Owen, Esq. F. R. S. &c. 



[Read before the Royal Society, March 21. 1844.] 



The fossil shell called Belemnite has long exercised the ingenuity 

 and research of the interpreters of ancient nature ; and although 

 sufficient evidence has, for some time, been obtained to determine 

 both the ordinal and family affinities of the organisation of the 

 animal constructing this singular compound shell, many additional 

 and important facts have been arrived at by the examination of 

 the well-preserved specimens from the Oxford clay, described in 

 this paper. 



In the compound shell of these specimens, the following parts 

 are recognisable : — 



1st. The terminal guard or sheath, resembling the head of a 

 dart or javelin, whence the name Belemnite was first given to this 

 part (which alone is generally well preserved), although it is now 

 extended to the animal. 



2d. The chambered or siphonated part of the shell called the 



I 4 



