48 MOLLUSCA FROM THE GREAT OOLITE. 
Evitrma communis. Plate IX, figs. 21, 21a. 
EL. Testé turritd, levigatd; spird regulari, obtusd ; anfractibus subplanis in etate 
juniori, etate progrediente convexis ; apertura ovatd ; labro tenui. 
Shell turreted, smooth; spire regular, obtuse; whorls rather flattened in the young 
state, but with advanced age more convex; aperture ovate; lip thin. 
When young the shell is much more flattened and obtuse ; but in all stages of growth 
the junctions of the whorls are strongly marked—the oldest specimens have the lines of 
growth strongly developed upon the last volution. The contrast between the peculiar 
flatness and almost conical figure of the young shells and older specimens which have lost 
their apex is so great, that without the assistance of intermediate forms they would 
probably be regarded as distinct species. The length never exceeds an inch. 
Locality. ‘This is decidedly the most common univalve of the Great Oolite, and occurs 
in all the shelly beds, more especially in the soft shelly Oolite beneath the planking at 
Minchinhampton Common. 
Eviima pyemma. Plate IX, fig. 1. 
LL. Testa levigatd, turrita ; spird obtusa ; anfractibus paucis, subplanis ; apertura sub- 
contractd. 
Shell smooth, turreted; spire obtuse; whorls few, nearly flat; aperture oblique, and 
somewhat contracted laterally. 
The last whorl is large, its length bemg half of that of the entire shell; the obtuseness 
of the spire, fewer volutions, nearly cylindrical figure, and obliquity of the aperture, 
separate it from 7. vagans. 
Locality. A single specimen is all we have met with: it occurred in the white stone 
of Bussage. 
Euviima vacans. Plate IX, figs. 3, 4. 
EF. Testé turritd, levi, elatéd; spird acutd, anfractibus paucis subplanis; apertura 
ovata ; labro deatro subexpanso. 
Shell turreted, smooth, elevated; spire acute; whorls few, high, and nearly flat ; 
aperture ovate; right lip somewhat expanded. 
The last whorl is nearly equal in length to all the others together. 
Locality. t occurs in the shelly planking rarely; and a few casts have also been 
obtained in the upper portion of the formation, east of Minchinhampton. 
