264 
AUG. F. FOEESTE 
The conch is compressed laterally, the lateral diameter at the 
aperture being 19 mm., the dorso-ventral one being estimated 
at 23 mm. The corresponding diameters at the base of the living 
chamber are 16 and 19 mm. respectively. The lower 9 camerae 
occupy a length of 14 mm.; the upper 3 camerae, however, 
occupy a length of only 3.8 mm., each being successively shorter 
and the uppermost being only 1 mm. in length, thus indicating 
that the specimen was mature. 
Along the dorsal side of the conch the sutures of the septa are 
almost directly transverse. On the lateral sides they curve at 
first gently downward, and then, on approaching the siphuncle, 
the sutures rise strongly upward. The septa, as far as known, 
are only moderately concave. The siphuncle has a lateral apical 
angle of 15 degrees. At the base of the living chamber its 
lateral diameter is 7 mm. At the base of the specimen its lateral 
diameter is 2 mm. The original length of the phragmacone of 
a complete specimen may have been 20 mm. The ventral side 
of the siphuncle apparently was in contact with the ventral 
wall of the conch along almost its entire width, thus agreeing 
with the latter in its lateral curvature. Along the side facing 
the interior of the conch, the siphuncle was more convex laterally, 
so that the cross-section of the siphuncle must have resembled 
somewhat that of a Tripteroceras, in the flattening of one side 
and the greater convexity of the opposite side. Between suc- 
cessive septa the walls of the siphuncle curve slightly inward, 
suggesting an Endoceratitic structure, successive funnels extend- 
ing downward the length of one camera and invaginating into 
the neck of the funnel next beneath. 
The cast of the interior of the conch is marked by faint vertical 
ribs, both on the phragmacone and on the living chamber, there 
being possibly 35 or 40 ribs within the circumference of the living 
chamber. Along the living chamber there are also several very 
faint annulations, with crests about 3 mm. apart. These annula- 
tions slope downward from the dorsal toward the ventral side 
of the conch at an angle agreeing with that of the margin of the 
aperture, but at a rate greater than that of the sutures of the 
septa. Whether these very obscure vertical ribs and transverse 
