RHYN CHONELLID BRACHIOPODS 
97 
PUGNOIDBS SOLON THOMAS AND STAINBROOK 
Plate I, Figs. 17 to 32. 
1921. Pugnoides solon T. and S. Science, New Series, Vol. LIV, 
p. 308. 
A strong shell of somewhat less than medium size, pentagonal 
in outline, wider than long, greatest width near the midlength. 
Pedicle valve produced in front into a broad extension which 
is deflected until at right angles to the plane of the valve; the 
deflected part is wider than long and is of nearly the same width 
throughout. Mesial sinus very broad and scarcely defined until 
a short distance above the deflected portion; at the geniculation 
the sinus is flanked by the sharply elevated but short bounding 
plications. Anteriorly the sinus bears two, three, or four plica- 
tions (rarely one or five), the greater number of shells have three; 
these are barely evident posterior to the deflected part. On the 
sides of the valve, near the margin, are three or four short, strong- 
ly elevated plications which give the sides a denticulated appear- 
ance. Beak closely incurved over that of the opposite valve ; fora- 
men small, terminal. 
O O 
A B 
<n> 
F 
Fig. 2. A series 
Pugnoides solon showing the dental lamellae of the pedicle valve and the median 
septum, crural cavity, and the crura of the brachial valve (x2j4). 
Brachial valve broadly convex from the umbo to the front mar- 
gin; sides sloping gradually, their surfaces convex; fold broad, 
flattened anteriorly and marked by two to five, (rarely six), 
short, somewhat angular, but stout plications which terminate in 
a strongly serrate edge. Lateral slopes marked by three or four 
plications which arise about halfway between the beak and the 
margin; they are more rounded than those on the lateral slopes 
of the opposite valve. 
of eight cross-sections of the rostral part of the shell of 
