188 
NArXILTODEA. 
Remarks. The species most nearly related to N. spirolohus are 
R. Sauperi, Hauer, N. Goniafifes, Hauer, aud i\". reticulatus, Hauer. 
From the first two N. spirolohus is distinguished by the character of 
Fig. 33. 
Nautilus {Clydonautilus') spirolohus. — a, lateral view, showing some of the 
sutures on the left-hand side of the figure, where the test is absent ; h, 
peripheral view, showing the sinus in the transverse ridges in the median 
line. Parts of the sutures (ventral lobes) are seen at the bottom of the 
figure. Drawn from a specimen in the Collection. About one-half 
natural size. 
its sutures, and from the last by its more involute and inflated 
whorls. 
Horizon. Upper Muschelkalk (Zone of Ceratites trinodosus). 
Locality. Somerau Kogel’, near Hallstadt, Upper Austria. 
Nautilus (Clydonautilus) Quenstedti, Fr. v. Hauer. 
1849. Nautilus Quenstedti, v. Hauer, Iseue Ceph. v. Hallstatt imd 
Aussee, in Haidinger s Naturwiss. Abhandl. Band in. p. 6, Taf. ii. 
ff. 1-3. 
1866. Nautilus Quenstedti, Dittmar, Zur Fauna der Hallstadter Kalke 
(geogn.-palaont. Beitrage, Band i. Heft ii. b), p. 342. 
1873. Nautilus Quenstedti, 'Mojsisovics, I)as Gebirge um HaUstatt 
(Abhandl. der k.-k. geol. Reichsanst. Band vi.}, p. 22, Taf. ix. 
ff. 1 a-c, 3. 
1882. Clydonautilus Quenstedti, Mojsisovics, Die Cephalopoden der 
Mediterranen Triasprovinz (Abhandl. der k.-k. geol. Reichsanst. 
Band x.), p. 281. 
Kofel or Kopf, the cone-like or sugar-loaf summit of a mountain. 
