146 
NAUTILOIDEA. 
well developed in this species, as the tubercles disappear in the 
older individuals, and an obtuse keel is present on the middle of the 
ventral part of the shell. The typical form of the species belonging 
to this group is only exhibited by Naut. tuber culatus^ Sow., itself, 
and from it the group can be traced without interruption up to the 
top of the Palgeozoic formations. The species which is most closely 
allied to the one described by Sowcrby is Naut. tuberculatus, Yer- 
neuil (non Sow.), the distinctness of which species from the true 
tuberculatus has been recognized long since by Prof. MoUer, without, 
however, his introducing a new name for it. It would be convenient 
to call this species Naut. Mdlleri, Waagen, l^ext comes Naut. 
Flemingianus, de Koninck, which is the geologically oldest species 
of the Tuberculatus group occurring in the Salt-range. DeKoninck’s 
original [specimen], which I am in a position to refigure, thanks to 
the liberality of the Geological Society of London, in whose collec- 
tion it has been preserved, comes from the middle region of the 
Productus-Limestone. This is followed by AVaagen, 
which species I shall have to describe hereafter ; it was found in 
the lower part of the upper division of the Productus-Limestone. 
A species which is again very nearly allied to Naut. Molleri, but 
easily distinguished by the more numerous tubercles, and which 
also very likely closely resembles young specimens of Naut. goJiathus, 
is Naut. multituberculatus, Waagen. It is the most recent species 
of the group in the Salt-range, and was found in beds at the very 
top of the Productus-Limestone formation. With this species the 
group of Naut. subtuberculatus seems to terminate, as no species, 
thoroughly allied to the group, has as yet been found in more 
recent formations.” 
The above was published (1879) before Mojsisovics’ Memoir upon 
the Cephalopoda of the “ Mediterranen Triasprovinz ” appeared 
(1882), in which there is no lack of species whose . affinities with 
those of the group of Nautilus iuberculati can be satisfactorily made 
out. Of these the following may be enumerated, viz., Temnoclieilus 
Neumayri.^ Mojsisovics, T. Morloti., Mojs., T. Cassianus, Mojs., 
T. Augusti., Mojs. \ and T. Scliloenbachi^ Mojs. 
The Triassic representatives of Temnoclieilus have much more 
embracing whorls than their congeners of the Carboniferous. Some 
Triassic forms make a very near approach in their squarish whorls 
^ Die Cepbalopoclen der Mediterranen Triasnrovinz (Abhandl, der k.-k. 
geol. Reiehs. 1882, Band x.), pp. 267, 268. 
^ Das Gebirge um Hallstatt, Band i. p. 12, Taf. ii. f. 1. 
