108 
[voL. XT IT. 
lieeonls of Oic Geological Snrreg of hidla. 
Upper Triassic limes, is a descendant from Pinacoceras is proLable. Tliei-e is au- 
ollier form which hears close resemblance to Otoceras, Goniatites mtumesens, Bey. ’ 
var. acutns, which is a close relation of it and belongs to the Devonian system- 
In external shape, thickness of shell, fine lines of growth and the shar]i-edgcd 
siphonal margin, they are all but identical, and from the figure (Ic) it scorns 
as if this species also, in a rudimentary stage, possessed the ear-like prolongations 
of the shell near the rimbilical region. Turning to the lobes we find also the 
first lateral saddle largely developed and turned towards the umbilicus, and an 
indication of a ^second lateral saddle, but the lobes terminate in simple sharjr 
points only, though corresjronding in general proportion. The line of projection 
of the preceding siphonal margin (vertical to the median plane) cuts through 
the second lateral lobe near the inner margin of the gi’eat first saddle. We have 
here the true predecessor of Otoceras in Devonian beds. 
The next younger form known is H'lmgaritcs (Oeratites) sfromiecM, Gi-iep.* 
from the lowest Wellenkalk of Brunswick, which shows many characteristics 
of my genus, but most so in the form of the lobes (fig. 3) which are nearly 
identical with mine. Apparently also the projection of the siphonal margin of 
the preceding whorl passes through the second lateral lobe. 
Whether the genus Iluugarites^ is a further development of Otoceras is not 
quite clear to mo, but the description of the lobes given by J. Biickh* seems 
to point to a relation with the older form of Otoceras. Mojsisovic" hints at the 
possible derivation of Pinacoreras from Goniatites ernaciatus, Barr.,® and indeed 
this species shows even greater likeness in general form and arrangement and 
position of the lobes to Goniatites intumescens, Bey., so that there is the indica¬ 
tion of a pedigree, which would stand thus : 
Siluriiiu 
Devoniiiu- 
... Goniatites ernaciatus, Barr. 
Carbuiis. ami Permian— 
tt'orfen beds- 
Lower fi’ellenkalk- 
Fitiacoceras Sagittarius 
Sageceras 
Gon. intumescens 
Carnites 
I 
Norites 
Otoceras 
Hungarites 
1 Saiidberger’s Verst. Rhein. Schiehtonsyst., Taf. VII, Sg. 1. 
^ Zeitsch. Dcutsch. Geol. Gesellsch., Taf. VII. 
2 Verb. Geol. Reichsanst., 1879, p. 140. 
^ Foldtani intezet, 1873, p. 166. 
Abb. Geol. Reichsanst., Bd. VI, p. 43. 
6 Syst. Sil., Vol. II, PI. III. 
