1889.] 
285 
[Foerste. 
septa are 4.2 mm. distant ; above and below these annulations con- 
traet regularly, connecting through the septa by apertures about 
3.2 mm. in diameter. 
Orthoceras (Actinoceras) lata-nummulatus, sp. nov. 
(PLATE VIII, FIG. 4.) 
The type specimen was found at the Soldiers’ Home, near Day- 
ton, O. In a length of 44 mm., it has nine chambers and ten septa. 
At the smaller end it has a diameter of 44 mm. ; at the larger ex- 
tremity the specimen probably had a width of 53 mm., as far as may 
be judged from the condition of the fragment at hand. The septa 
are strongly concave, forming an arc of about 134°. The siphon 
is central, having broad annulse between the septa, 11 mm. broad 
where the diameter of the shell is 47 mm. ; the corresponding 
height of the annuls® being 4.2 mm., the distance between the an- 
nulae .4 mm., the siphon narrowing abruptly between the annulse to 
a width of 4.2 mm. The entire margin of the annulse above the 
middle is sometimes notched by an annular groove, along which a 
suture often divides the annulse into upper and lower halves. The 
surface of the shell is unknown. 
This species may be distinguished from 0. Youngi by means of 
the much broader annulations of the siphon, a slightly smaller ap- 
ical angle and a greater concavity of the septa. 
Orthoceras (Actinoceras) turgid a-nummulatus, sp. nov. 
(plate VIII, FIG. 7.) 
The type specimen was found at Soldiers’ Home, near Dayton, 
Ohio. The specimen is 38.5 mm. long and contains in that length 
ten chambers and eleven septa. The diameter of the shell at the 
smaller end is calculated to be 8.2 mm., as far as may be judged 
from the remainder of the shell preserved. The diameter of the 
larger extremity is 23 mm. The septa are moderately concave, 
forming an arc of 118°. The siphon is central or almost central, 
forming annulations between the septa having a diameter of 5 mm. 
where the diameter of the shell is 8.2 mm., and the distance be- 
tween the septa is 3.4 mm. ; where the diameter of the shell is 19 
mm., and the distance between the septa is 3.8 mm., the diameter 
of the annulation of the siphon is 5.6 mm. The siphon decreases so 
abruptly in size between the annulations that the annulations seem 
to be separated only by a distance of .2 mm. along plane surfaces 
