NAUTILID^. 
235 
with a kuife ; the other system of striae then entirely disappears. 
. , . On the cast the normal line is often very strongly pronounced.’ 
Remarlcs. “ This species is rather near to X. lineatus, but it is 
distinguished by its more sinuous and approximate septa and nar- 
rower umbilicus. 
“ The differences which separate the present species from N. liecca- 
(foniis^ J. de C. Sowerby, have been pointed out by that author in 
his description of the Kutch fossils collected by Captain Grant b 
He says, ‘ This [JV. liexagonus ?] differs from N. hexagonus in 
having a smaller umbilicus and in being more rounded.’ 
“ Oppel distinguished this species from Sowerby’s by its wider 
aperture; it may also be known by its deeply-lobed sutures, in 
which character it approaches Nautilus {Hercoglossa) Franconicus^ 
Oppel.” (^Foord and G. C. Crich.) 
Horizon. Calcareous Grit and Xelloway Hock. 
Localities. Wiltshire ; Marcham, Berkshire (Calcareous Grit) ; 
Scarborough, Yorkshire (Kelloway Hock). 
Well represented in the Collection. 
Nautilus hexagonus, J. de C. Sowerby. 
1825. Nautilus gigas, d’Orbigny, Amiales des Sciences Natiirelles, 
vol. V. pi. vi. f. 3. {Not of Zieteii.) 
1826. Nautilus hexagonus^ J. de C. Soverby, Min. Conch, vol. vi. p. 55, 
pi. dxxix. f. 2. 
1835. Nautilus hexagonus ?, Phillips, Geology of Yorkshire, 2nd ed. 
pt. i. p. 113. 
1841. Nautilus Williamson, Trans. Geol. Soc. ser. ii. vol. vi. 
pt. i. p. 152. 
1842. Nautilus gigajiteus, d’Orbigny, Paleontologie Fran^aise (Terrains 
Jiirassiques), vol. i. p. 163, pi. xxxvi. 
1845. Nautilus hexagonus ?, Murchison, Outline of the Geologj'- of the 
Neighbourhood of Cheltenham, new ed. p. 80. 
1849. Nautilus giganteus, d’Orbigny, Prodrome de Paleontologie Strati- 
graphique, vol. i. p. 348. 
1852. Nautilus hexagonus^ Giebel, Fauna der Vorwelt, Band hi. 
x\bth. i. p. 155. 
1854. Nautilus hexagonus^ Morris, Catalogue of British Fossils, 2nd ed. 
p. 307. 
1858. Nautilus hexagonus, Ooster, Catalogue des Cephalopodes, Fossiles 
des Alpes Suisses, pt. iii. p. 8. 
1859. Nautilus giganteus, Thurmann et Etallon, Lethea Bruntriitana, 
p. 74, pi. i.f.2. 
Trans. Geol. Soc. ser. ii. vol. v. pt. ii. 1840, Explanation of Plates. 
