162 
NAUTILOIDEA, 
form of Naut. latissimiis is very remarkable for a certain similarity 
to those species of Nautilus which have been considered by Q,uen- 
stedt as forming his group of the Moniliferi. If we compare speci- 
mens of Nautilus hidorsatus, Schlotheim, we find that the general 
form of the shell agrees pretty well with that of the full-grown 
shell of Naut. latissimus, only the whorls are broader and the 
outer edge of the whorls is less angular in the latter than in 
Schlotheim’s species. The directly connecting links between the 
two species, however, are absent, and thus it cannot be ascertained 
whether we have to deal here really with the ancestor of those 
Triassic forms or not, but the similarity must not be lost sight of.” 
Another species having a considerable resemblance to the present 
one is the Nautilus canaliculatus of Cox 
Horizon. Muschelkalk 
Localities. Niederbronn, Elsass ; Erkerode, Brunswick ; Weimar, 
Saxony ; Aach, W iirtemberg. 
Temnocheilus nodosus, Munster, sp. 
1831. Nautilus nodosus, Munster, Bull. Soc. Geol. de France, tom. i. 
p. 182. 
1832. Nautilus nodosus, Goldfuss, in von Dechen’s translation of De la 
Beebe’s Handbook of Geology (Handbuch der Geoguosie), p. 4o6. 
1837. Naidilus nodosus, Broun, Lethma Geognostica, Band i. 2nd ed. 
p. 176. 
1849. Nautilus hidorsatus nodosus, Quenstedt, Petrefactenkunde Deut- 
schlauds. Band i. Abth. i. p. 54. 
1883. Solenoceras nodosum, Hyatt, Proc. Boston Soc. Nat. Hist, 
vol. xxii. p. 286. 
Sp. Char. This species appears to resemble Temnocheilus hidor- 
satus in every respect except that it is ornamented with a row of 
strong, flattened nodes along each edge of the periphery. These 
nodes are described by Quenstedt as being fewer in number than 
the septa, and more distinct in the young than in the adult period 
of growth. The lines of growth make a very strong backwardly- 
directed sinus upon the periphery. Quenstedt adds that the 
^ GeoL Surv, Kentucky, 1857, vol. hi. p. 575, pi. x. ff. 3, 3a. 
^ The Muschelkalk is separated by the German geologists into three 
divisions, viz. Lower Limestone (Wellenkalkgruppe), Middle Limestone and 
Anhydrite (Anhydritgruppe), and Upper Limestone (Hauptmuschelkalk). The 
middle division, consisting of dolomites with anhydrite, gypsum, and rock- 
salt, contains very few fossils. Temnocheilus hidorsatus occurs both in the 
Lower and Upper Divisions of the Muschelkalk. See Oredner, ‘Elemente der 
Geologie,’ 6th ed. 1887, pp. 554-557. 
