ialontolngia ndita,

- .
176 REVISION OF THE JURASSIC CEPHALOPOD
nian assemblage that included forms of the type of ' Stephanoreras ' eszterense
{Boeckh) and the ' bullat '.
We cannot, . thus, agree with Loczy (1915, p. 443) who stated that Macrocephalitids,
in India, appeared already in the Lower Bradfordian (=zone of
Parkinsonia ferruginea) and therefore 'had their origin in that area.
Kheraiceras is more or less homoeomorphous with its forerunner, Bullatimorphites,
but apart from the di:fferences in the suture-line and evolution, the
earlier wh9rls of the former are almost cadoceratid, those of the latter sphaeroceratid.
Reinecke's Nautilus platystomus of Reineckeian age with a somewhat
cadoceratid whorl-shape has already been stated to be a Pleurocephalites, close
o P. tumidus, but Quenstedt's Amm. platystoma, previously referred to (Spath,
1925b, p. 16) and Roemer's Bat_honian forms (191 1, pp. 41-43, pl. VII, figs. 15-
22, pl. VIII, fig. 1) include various transitions from Bullatimorphites to Kheraicems.
Similar forms have recently been quoted again · by Lissajous (1923, pl.
XIX, figs. 1-3) and Bataller (1927, p. Ill) as 'Sphaeroceras ' platystoma,
Reinecke sp. from the Upper Bathonian of France and Spain.
The genus Bullatimorphites is included by Mr. Buckman in Tulitidae, but
it is also connected with Sphaeroceratidae, whereas Amm. morrisi, Oppel (=MOTrisites
[+ Morrisiceras] Buckman = Prionoceras, Lissajous, non Hyatt nee Buckman)
is more intimately connected with some Macrocephalitid offshoots here
discussed. Whether M OTrisites be -·assigned to Macrocephalitidae or T litidae
·may be a matter of perEonal opinion, but the latter family cannot compare
in importance with the former, being in fact based largely on individual variations
of one species, Ammonites subcontractus, Monis and Lycett, that have
'been unduly raised to generic · rank. · Tulitids are a· horizontally limited offshoot
of the persisting · Stephanoceratid stock ; in the Mediterranean Province there
is apr arent .conti:p.uity from Sph aeroceras, or possibly Emileia (Pompeckj, 1894,
p. · 255) to Mactocephalites. Although we must ·reject Hyatt's 'evidence ' of a
tuberculate ancestor of Macrocephalitids and his '· gradual ' increase of lateral
cc mpression, it is probable that Sphaercceras itself is not the root form of all
Macrocephalitids.
The Macrocephalitids of Kachh belong to the following six genera and
nineteen specieB :-1
Genus · Maci-ocephalites (v. Sutner MS) Zittel.
M. fOTmosus (J de C. Sowerby).
M. chariensis (Waagen).
M. trian!fl.daris sp. nov.
M. ·madagascariensis, Lemoine.
·Genus lndooepJ.alites Spath.
I. transitorius, ·sp. nov.
· I: kheraensis, Spath.
I. chrgsoolithicus (Waagen).
I. diadematus (Waagen).
1-. indicus sp. nov.
1 Oeeoptgchi!U ,.ej'rwbl.8 lteineoke has now to be added (June, 1928 : see pp. 252, 277).