ialontolngia ndita,

REVISION OF THE JURASSIC CEPHALOPOD
as the lectotype af Boehm's species, namely his pL XXXVI, figs. 3a, b, diffe:ra
in being still more finely costate. The evolute form :figured by Boehm (1912a)
in pi. XXXVIII. :fig. 1 is transitional to Eucycloceratid.s, as his pi. XLI, fig. 3
':!onnects with the ancestral J.liacrocephalites of the madagascariensis-type.
The more evolute Dolikephalites dolius, Buckman, like others of the numerous
Cornbrash examples · probably merely an individual variation of Dolikephaliles
typicus (Blake), shows recticostation almost to the end and the typical
forward projection of the peripheral ribs, if appearing at' all, is confined to
the vicinity of the aperture as in the equally transitional group of Kamptokephalites
lamellosus.
Noetling's Mazar Drik form almost certainly does not belong to Waagen's
species ; and Burckhardt's {1900, p. 11, pl. XIX, figs. 7-8) 'Sphaeroceras subcomp1·essum
', later (1903, p. 31, pl. Ill, figs. 5- 6) renamed Macrocephalites
noetlingi, is also closer to the group of Kamptokephalites lamellosus than to
Dolikephalites subcompressus.
On the other hand these two species are undoubtedly closely allied, as
W aagen already noticed. There is a body-chamber fragment which shows even
closer costation than that author's type of the present species, but has a less
compressed whorl-section. It may well represent merely a finely ribbed extreme
of the same gens as his ' Stephanoceras subtrapezinum ', . with similar ornament
on the body-chamber.
The small example figured on pl. XXVII, fig. 4 represents the inner whorls
of a doubtful form, the corroded and fragmentary (unfigured) outer whorl of
which shows a steeper and higher umbilical wall than the present species or
Kamptokephalites lamellosus var. aureus ; it may seem referable to either. The
bundling of the primary ribs of the inner whorls however, is peculiar and
resembles that of immature Dolikephalites from the English Cornbrash, although
in these the ribbing is not projected on the periphery. The inner whorls of ·
the holotype of D. subcompressus certainly do not show bundled primary ribs
so that this specimen may well belong to a new species.
Hon:zon.-Lower Callovian, dimerus zone 1
Localities.-Waagen recorded this species from north-west of Soorka and
some specimens (probably transitional to Kamptokephalites lamellosus) from
Jooria and Khera. The additional examples here recorded (J. H. Smith Colln.,
Nos. 109 and 133) are from the Habye Hills.
Genus : KHERAICERAS Spath.
KHERAICERAS COSMOPOLITA (Parona and Bonarelli).
(Pl. XLVII, fig. 6).
1875. Stephanoceras bullatum (d'Orbigny) ; Waagen, p. 129, pi. XXXII, fig. I.
1A.97. Sphaeroceras cosmopolita, Parona and Bonarelli, p. 146.
1923. Sphaeroceras co81tWpolita, Parona and Bonarelli ; Lissajous, p. 92, non pi. XIX,
fig. 5.
l924:. Kheraiceras cosmopolita (Parona and Bonarelli) ; Spath, p. 7.
l!l25 Kheraiceras cosmnpolita (Parona and Bonarelli) ; Spath, p. 15.