2\"eir Fossi/s ffom J/isxo/iri. — Jioir/eif. ^>21 
basal plates. The edges of the radial pieces and basal plates 
^t their union form a slender double ridge, quite noticeable. 
The radial plates extend upward almost to the flattened top. 
Interradials occupy a space at the top larger than the area 
occupied by the basal plates at the other end. A slightly ele- 
vated double ridge follows the radio-interradial sutures, but 
no such elevation can be seen along the sunken radial sutures. 
Fine granular lines parallel to the ambulacra ornament the 
radial plates. The edges of the radials at the ambulacra are 
bent so abruptly upward as to appear to be bounded below by 
a suture. The ambulacra occupy less than three-fourths of 
the hight of the body, are very narrow with numerous pore 
pieces either side of the mesial furrow. The azygous interra- 
dial is little, if any, larger than the other four interradials. 
Anal opening rather large. Ovarian openings eight in number, 
rather small. Central opening uncovered in the specimens. 
This blastoid may belong to Dr. Carpenter's genus kSchizn- 
blastus, as it seems to present some outward resemblance to it. 
The collection contains nine specimens preserving the test 
and ten or more tine natural casts, some of which are larger 
than figure 14, all very striking fossils because of the great 
elevation of the ambulacral ridges which are extravagantly 
high above the sunken radials in the largest casts. One only of 
the casts is sub-elliptical in outline, while all the others 
eagre with the specimens figured, and all have a more or less 
distorted appearance, hardly accidental. 
Collected from the upper Burlington limestone aiul the 
cherts of that horizon, just above the ActiiiocriiiHs sclfuhis ho- 
rizon and consequently at the very base of the upper Burling- 
ton, in the quarries at Louisiana, Mo. Found associated with 
Sc}uzobIa.stiis sftt/i, /'/ii/sefocrinii.s- rent ricosiis and other w«"ll 
known upper Burlington forms. 
GONIATITES LOUISIANENSIS. sp. nov. 
Fig. 15. The largest specimen found, natural size. Figs. IG to 18. 
Enlarged views of the same specimen. 
Shell compressed, very small. Uml)ilicus large aiul rather 
deep, but the condition of the specimens is such that the iniu'r 
whorls are not visible. Volutions rather slender and rounded 
on the dorsal side. Septa distinct only in a few s))eciniens, 
probably on account of the pyritized condition of the shells 
Dorsal lobe long, tongue-shaped aiul roundeil at the end. Dor- 
