17 



Fig. 9. 



mon fossils are the Ammonites (fig. 9), named from the circumstance 

 that they resemble the ram's horn found on the 

 statues of the old heathen deity, Jupiter Amnion, 

 and also from the fact that they had in idol times 

 (so it is asserted) a place in the worship of that 

 deity. Not unlike a coiled-up snake 1 in con- 

 tour, the belief came that they were stony ser- 

 pents converted to this rigid form, as a judg- 

 ment on their evil deeds. Sir Walter Scott 

 has charmingly described to us in the poem of 

 Marmion 2 that 



" "Whitby's nuns exulting told, 



Ammonites interruptus, 

 a Gault form. 



Fig. 10. 



And how, of thousand snakes, each one 

 Was changed into a coil of stone 



When holy Hilda prayed ; 

 Themselves, within their holy bound, 

 Their stony folds had often found." 



Marvellous as seems the tale, still more marvellous is the Ammon- 

 ite itself ; in plan and in design exhibiting a most complicated in- 

 ternal structure and lovely outside pattern. Similar to the Nautilus 

 in the possession of sets of chambers, and of a 

 communicating hollow pillar (this tube being in 

 the Ammonite on the outside of the rooms), it also 

 surpasses the Nautilus in the intricacy and undula- 

 tions of its floors (fig. 10), so involved and so ar- 

 ranged that they form a petaloid figure — a contour 

 appearing on and intersecting the outside surface 

 of the walls, something after the shape of those 

 divisions on our skulls called sutures. 



I fear that words cannot express the ideal plan ; 

 but if you will conceive the floor of a room to undu- 

 cross waves, and if you will imagine each 



View of the undu- 

 dulating partitions 

 (Septa) dividing the 

 shell of the Ammon- 

 ite into chambers ; 

 drawn from a speci- 

 men of A.interrupt.us 

 from Gault of Bon- 

 church, Isle of Wight. 



late, say in two 



1 This is especially true of the common Whitby species, Ammonites communis, 

 with the small exception of being destitute of headpiece ; a difficulty the Yorkshire 

 curiosity-dealers overcame by carving the requisite member. See a picture of 

 one in Sowerby's Mineral Conchology, Plate 107, fig. 2. 



2 Canto ii. 13. The same tradition is described as an ancient belief by J. de 

 Laet, in his Book on Gems, p. 109, 1G47. 



2 



