760 Report or THE State Gxoxroaist.. 
Syringothyris, Winchell. 1893. 
(Plate 30, figs. 1-11.) 
Shells spiriferoid, usually large, with erect cardinal area and 
broad, multiplicate lateral slopes. Fold and sinus generally non_ 
plicate. In the pedicle-valve the delthyrium is covered by a 
convex, imperforate plate, which is frequently absent. The 
dental lamella, more or less strongly developed, rest on the bot_ 
tom of the valve, and at their anterior extremities are produced 
about the broad diductor impressions. They are united beneath 
the deltidium by a transverse plate arising from a testaceous 
callosity in the apex of the delthyrium. This plate is formed by 
the deposition of accretions to the margins of the delthyrium, 
which unite in the median line, the union being marked by a 
raised line less distinct on the upper than on the under side of 
the plate. From just within the lateral margins and on the 
inner side of the plate two processes are given off, which are 
curled toward each other with some irregularity, not meeting 
except where coalesced with the apical callosity, forming a tube 
which is split along its inner surface. This tube is adherent to 
the transverse plate as far as the latter extends, and is frequently 
produced beyond its termination. 
Muscular scars as in Spreirer, their anterior portion being 
divided by a short median septum which is an extension from 
the apical calcareous deposit. 
The brachial valve is spiriferoid in all internal details. The 
cardinal process is broad, multistriate and supported by a short 
median thickening. The spirals are large, the 
primary lamelle bearing a pair of short, dis- 
crete spinous processes which represent the 
jugum. The shell structure is more or less 
distinctly and abundantly punctate. It is 
probable that these puncte perforate the 
Fia. 287, The primary = . 
lamell of Syringothyrie ©Pidermal layer and extend to the inner 
qyna. lamella of the shell. The exterior is usually 
covered with a finely textile ornament which has been compared, 
in appearance, to “twilled cloth.” 
Type, Syringothyris typa, Winchell. Burlington limestone. 
Distribution. Carboniferous. 
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