_ SHUMARD AND SWALLOW—NEW FOSSILS. 225 
with nearly equi-distant, short, flattened, thorn-like processes, 
which rise from a base and are directed obliquel up- 
ward. These thorns, of which from twelve to fourteen may 
be counted on either side of the spine, do not ri m the 
same horizontal line, but the bases of those of om ne are 
higher than those of the other. The engi part of the 
base of the ge is mar ee with coars and more re distinct 
strie 
strongly and Wit striated. 
Dimensions —Width of sitcdaabteatel a late, .24; ee 
18; length of primary spines, about 24 inches; diameter. 
ay tg pore: 10 
Geol. Pos. and Loc.—This beautiful species was collected by 
Prof. Swallow i in the Middle Coal asures, at Lexington, 
in thin on Aaah of limestone g beds of shale. 
Mis 
is semacdaied with Fusulina NTS Choneles Smithii, 
and ¢ Orthisina Miss souriensis. 
ARcH£ocIDARIS MEGASTYLUS, Shumard. 
. 
The interambulacral plates of this species in the collection 
are wlan hexagonal, wider than long, and rather thick. The 
areolar surface is ied broad, nearly circular, slightly concave 
at its exterior portion and rising gently to the base of the cen- 
pads ‘Ain encoded by asingl sre of small, secon secondary 
ercles. The boss is broad, smoot h, and the central tuber- 
long, robs eylindrieo-fusiform, 
ireular e surface et fae 
