oo / | 
EXPLANATION OF PLATE XXII. 
’ 
oe Figure 1. QuapruLa uNpULATA Barnes. Juvenile. = 
| ; g baat 2 
ty : ‘© 2. QUADRULA UNDULATA Barnes. | Kos 
may ‘« 3. ALASMODONTA MARGINATA Say. — 
; ; 34 natural diameter. 
