158 
NAUTILOJDEA. 
1848. Nautilus Freiesleheni, Kinpr, Cat. of tlie Organic Remains of the 
Permian Rocks of Northumberland and Durham, p. 14. 
1849. Nautilus Freiesleheni, d’Orbigny, Prodr. de Paleont. Straligr. 
vol. i. p. 163. 
1850. Nautilus Freiesleheni, King, Monograph of the Permian Fossils 
of England, p. 219, pi. xvii. ff. 13-16, and f. 20 (named in the 
description of the plate Nautilus Boioerhankianus). 
1851. Nautilus Freiesleheni, Griinewaldt, De Petref. form. calc, cuprif. 
in Silesia, pp. 10 and 40. 
1852. Nautilus Freiesleheni, Giebel, Fauna der Yorwelt, Band iii. 
Abth. i. p. 146. 
1854. Nautilus Freiesleheni, Morris, Cat. British Foss. 2nd ed. p. 308. 
1857. Nautilus Freiesleheni, Howse, Ann. Mag. Nat. Hist. vol. xix. p. 43, 
pi. iv. f. 26. 
1861. Nautilus Freiesleheni, Geinitz, Dyas oder die Zechsteinformation 
imd das Rothliegende, Ileft i. Die Animalischen Ueberreste der 
Dyas, p. 42, Taf. xi. IF. 7, a-c. 
1885. Nautilus Freiesleheni, Tschernyschew, Verhandl. der russisch- 
kaiserlichen Mineralogischen Gesell. zu St. Petersburg, ser. ii. 
Band xx. p. 268. 
1886. Nautilus Freiesleheni, Zimmermann, Jahrb. der konigl. Preuss. 
geol. Landesant. und Bergakad. zu Berlin fiir das Jahr 1885, 
p. 107. 
Sp. Char. Shell deeply iimbilicated on both sides, the whorls 
much broader than high. Periphery broad and flattened, with 
rounded angles, the sides spreading outwards towards the umbilical 
margin. The septa are rather distant from each other and form a 
shallow sinus on the sides and periphery. The siphuncle is 
situated a little below the centre of the septa. The test, which is 
thin, is ornamented with delicate lines, which form a backwardly 
directed sinus upon the periphery. In young examples the test is 
covered with very fine longitudinal lines, but these become indis- 
tinct as age advances, and they finally disappear entirely. 
Remarks. Prof. King (Permian Fossils, p. 220) observes that 
“ Nautilus concavus, J. de C. Sowerby, of the Carboniferous System, 
appears to be a closely related species.” 
Nautilus Freiesleheni is found in England, according to King, in 
Shell-limestone at Humbleton Quarry, Tunstall Hill, Silks worth, 
and Dalton-1 e-Dale (Durham) ; and in the compact beds at "Whitley 
Quarry (Northumberland). Geinitz records it from the following 
localities in Germany : — In the Lower Zechstein of Gera (Reuss) ; 
in the Kupferschiefer of Milbitz (Schwarzburg-Rudolstadt) and 
Trebnitz (Silesia) ; in the Lower Zechstein of Trebnitz, Corbusen 
(South Altenburg), &g. Large specimens are found in the Lower 
Zechstein of Ilmenau in the Thiiringer Wald, at Setters (Hessen- 
