“ SHUMARD—-NEW PALAOZOIC FOSSILS. iis 
ELMACRINUS KIRK WOODENSIS, n. sp, 
Body very small, subglobose, a little longer than wide, flat- 
tened above and below. Basal pieces very gently coneave, 
with their edges on a level with the plane of the under side, 
Radial pieces (fork pieces) reaching to the base and oceupy- 
ing more than four fifths the entire length of the body, narrow 
below and widest in the middle, sides gently arched. Interra- 
dial pieces subdeltoid, very prominent towards the apex, much 
longer than wide, obtusely angulated below, acutely angulated 
above, and notched on either side short distance below the 
summit. Pseudo-ambulacral”areas extending from base to 
summit, narrow, deeply impressed; sides nearly parallel; pore 
_ pieces amounting to abont fifty in each field. A longitudinal 
fissure or slit extends from the central summit opening down- 
wards, separating the pore pieces of one side from their fel- 
lows of the opposite for the distance of about one fifth the 
Jength of the field, thence their inner edges are united in the 
median line to thé base. Pseudo-ambulaéral spaces lancéo- 
late, sloping gently from their edges to the sutures. Ovarial 
apertures ¢ight, very minute, situated at the notches of the 
interradial plates. Anal opening large, circular or very slight- 
ly elliptical. The surface markings are not plainly exhibited 
in any of the specimens I have collected of this species. On 
several of them I observe, more or less distinctly, irregular 
eoarse ruge. or -pittings, which, however, may be due to. weath-.- o 
ering . . - ee a : 
Dimensions.—Leneth, O20 ofan inch; width,018.  . 
The Hlewucrinus Nirkwoodensis is pearly alhed to # 
(Pentremites) melo, trom which it is distinguished by its 
much smaller size and less deeply excavated base. It alse 
occupies a higher geological position, —_. 
Occurs in the St. Louis Limestone (Carboniferous) on the 
Pacific railroad near Kirkwood, St. Louis county, Missouri. 
