AMERICAN PALEOZOIC CEPHALOPODS 
235 
In Litoceras Hyatt, the cross-section of the conch is broadly 
kidney-shaped; the ventral side presents a semicircular outline, 
which rounds rapidly into the broadly impressed dorsal side of 
the conch. The siphuncle is located distinctly dorsad of the cen- 
ter, except in younger stages of growth. Since the genotype, 
Litoceras whiteavesi Hyatt, is from the Canadian of Newfound- 
land, it may be assumed that the segments of this siphuncle were 
curved cylindrical, and not elongate elliptical or subfusiform in 
outline. Litoceras does not occur in the Richmond formation. 
Charactoceras includes also Nautilus Hercules Billings, from 
the Charleston formation (Richmond) of Anticosti. Eurysto- 
mites plicatus Whiteaves, from the Lake Winnipeg area, appar- 
ently is congeneric. 
33. CHARACTOCERAS BAERI (MEEK AND WORTHEN) 
PLATE XXXI, FIG. 1; PLATE XXXII, FIGS. lA, B; PLATE XXXIII, 
FIGS. lA, B; PLATE XXXIV, FIGS. lA, B, 2 
Trochoceras (?) Baeri Meek and Worthen, Proc. Acad. Nat. Sci. 
Philadelphia, 1865, p. 263. Meek, Geol. Surv. Ohio, 1, 1873, 
p. 157, pi. 13, fig. 9. 
Tijpe specimen. — The type was collected at Richmond, Indiana. 
It con-sisted of a phragmacone, defective on one side, showing 
neither surface structure, nor the siphuncle. The dorsal side of 
each volution is impressed distinctly by the ventral side of the 
preceding volution. The type is illustrated in volume 1 of the 
Paleontology of Ohio, and in this volume it is stated that frag- 
ments from the same locality and position as the type have the 
siphuncle located rather more than its own breadth outside of the 
center. Better specimens, collected by Prof. W. H. Shideler from 
the Richmond at Oxford and vicinity are described in the fol- 
lowing lines. 
Oxford specimens. — Maximum diameter of the largest well 
preserved specimen found, (Plate XXXI, Fig. 1; Plate XXXII, 
Figs. 1 A, B; see also Plate XXXIH, Figs. 1 A, B), from the 
ventral margin of the aperture to the opposite side of the last 
volution, 150 mm. ; diameter at right angles to the latter, also 
across the umbilicus, 113 mm. Lateral diameter of the living 
chamber at the base of the hyponomic sinus, 93 mm. ; dorso- 
ventral diameter at the same point, 66 mm. Length of living 
chamber from suture at base to lower part of hyponomic sinus, 
measured along the ventral side, about 100 mm. ; length to highest 
