68 AMMONITIDA. 
into a broad, short lobe. The last whorl frequently differs in 
form and sculpture from the inner whorls. The lobes are dis- 
tinguished by their broad saddle stalks, with divisions cut in 
obliquely, the oblique position of the tips of the lobes, great 
development of the principal lobes, and striking reduction of 
auxiliary ones. 
HALORITES, Mojs., 1879. Body-chamber and spiral of the 
whorls as in Arcestes. Inner whorls with granulose ribs ; saddles 
elevated, with many narrow lateral branches; lateral lobes 
reduced ; last whorl with a different form and sculpture from the 
others ; aperture a little contracted ; a wrinkled layer present. 
JUVAVITES, Mojs., 1879. Differs from Halorites by its last 
whorl resembling the preceding ones, and its less dentate lobes ; 
the shell bears traces of periodical contractions. 
DISTICHITES, Mojs., 1879. Convexity of the shell with a median 
groove, usually bordered by carinz; inner whorls having the 
ornamentation of 7. Jockelyi; last whorl with additional ribs 
intermediate to those which ornament the preceding whorls; 
body-chamber occupies more than a whorl; lobes as in Sagenites. 
Evutomoceras, Hyatt, 1877. 
Distr.—E. Laubet, Meek (xxxvii, 6,7). Trias; Nevada. 
Characterized by its lenticular form, narrow umbilicus, appa- 
rently at all ages very sharp external keel, without furrows or 
lateral ridges, and small regular arched pile on middle-sized 
Specimens, growing wider, more irregular, less distinct, and 
developing small lateral lobes on the adult, with both nodes and 
pile becoming obsolete on the larger part of the body-volution. 
Ceratitee. 
CERATITES, de Haan., 1825. 
Syn.—Haaniceras, Bayle, 1878. 
Distr.—Permian, Trias. The Cretaceous forms referred to 
Ceratites perhaps belong to another group. C. nodosus, Brug. 
(GexxT;'23): 
Shell discoidal, more or less sculptured ; sutural line with 
simple, rounded saddles, and shallow denticulated lobes; anti- 
siphonal lobe doubly toothed. 
TIROLITES, Mojs., 1879. Lobes not toothed, or showing the 
commencement of teeth; second lateral lobe more or less sal- 
lent; convexity of the whorls smooth, rounded, nearly flat. C. 
Idrianus, Hauer. 
BALATONITES, Mojs., 1879. Periphery with a tuberculated 
carina. C. Balatonicus, Mojs. 
HUNGARITES, Mojs., 1879. Shell narrow, with a much elevated 
median carina; lobes as in Ceratites. C. Zalaensis, Bockh. 
ACROCHORDICERAS, Hyatt, 1877. This group is closely allied to 
