110 
Plate VI 
Palliseria robusta Wilson 
Figure"!. Natural section of two specimens, the lower one showing the six angles of the section, 
and the umbilical ridge projecting into the umbilicus. The upper specimen is not quite perpen- 
dicular. (Page 30.) 
Figure 2. Opposite side of figure 1, showing the broad, flattened, band-like area on the last whorl, 
and the surface markings across it and on the under side. (Page 30.) 
