PLATE XXXIV. 
Zone of Aegoceras Henleyi. 
Fig. 1. Aegoceras maculatum. Young and Bird, Lateral view, natural size. The 
figures in this plate are 
arranged to show that Aeg. 
maculatum. Young = Aeg. 
capricornum, Schloth, of the 
Yorkshire coast, is the imma- 
ture condition of Aegoceras 
heterogenum. Young and Bird, 
found in the same beds. 
2. — — - — Siphonal area of the same shell. 
3. — — — Front view of do. do. 
4. — — — Specimen in which the trans- 
formation scene in the last 
whorl has been nearly accom- 
plished. 
5. — — — Front view of the same fossil. 
6. — — — Siphonal area, showing the re- 
markable change in the ven- 
tral area both in width, tuber- 
cles, and ribs. 
7. — — — Accurate tracing of the lobe- 
line. 
8. — — — Do. do. another 
specimen. 
All the specimens figured in this plate belong to the Leckenby collection, Wood- 
wardian Museum, Cambridge. 
