Subject ASC0001t5b
The Quarterly journal of the Geological Society of London.
v.53 (1897), Page 189 (1897)
Smithsonian Libraries
BHL Page 36028962
Keywords
fossils.graptolite identification classification Petalograptus folium growth form theca Petalograptus-Folium sicula rhabdosoma Diplograptus G.L. Elles biology early stage magnify magnified view spine apertural primordial bud