ORIGINAL ARTICLES. 
The Use of Graphs in Palaeontology 
By H. H. Swinnerton, D.Sc., F.G.S., F.Z.8., Professor of Geology, 
University College, Nottingham. 
(Concluded from p. 364.) 
EXAMPLES FROM CARBONIFEROUS CORALS. 
To illustrate the value of graphic methods when changes in a 
number of distinct structural elements are studied, examples may 
be taken from the Carboniferous corals. These are well suited to the 
purpose, because thin slices yield so much information and are easily 
measured. In Fig. 4 a diagrammatic section is shown of one of the > 
most highly organized corals, which exhibits the following important 
structural units: epitheca, tabule, septa, dissepiments, tabelle, 
lamellae, columella. 
Fic. 4.—Diagrammatic section of Dibunophyllum showing the structural 
elements with which it is constructed. ep. epitheca, J. lamella, tb. tabella, 
col, columella, s'. major septum, t. tabula, s?. minor septum, d. dissepiment. 
As shown by the accompanying table (Table I), the mere presence, 
or absence, of one or more of these units constitutes an important 
diagnostic feature for many genera. This table shows that these 
Tabulae. Septa. Post Tabellae. Lameltae, Columelta| 
Favosiles. 
Zaphrenhs. 
Caninia. 
Cyathophyllum. 
Aulophyllum. 
eee 
LiFhostrohien. 
Cystiphyllum. 
Duncanella. 
TABLE I.—This illustrates the combinations of structural elements present in 
various corals. x element present, — element absent. 
