OF THE CATAMITES OF THE COAL-MEASUEES. 
507 
he naturally objects to my employing his name in a new sense. Under these circum- 
stances I propose designating all the plants which have no infranodal canals, indicated 
by the absence of verticils of round or oblong scars, Catamites, whilst to those which have 
possessed such canals, I would assign the name of Catamopitus , already applied to them 
in my previous memoir on the subject. 
I am disposed to regard all existing specific names and definitions as worthless. They 
separate things that I believe to be identical, and confound others that are obviously 
distinct. The medullary casts, with their altered carbonaceous coverings, appear to afford 
very imperfect data for the determination of species. Practical purposes may require 
the provisional employment of a few such names, but they have little if any scientific 
value. One remarkable plant has been included amongst Catamites which I believe has 
no affinity with them, — I refer to the Catamites verticitlatus. 
I have to acknowledge the kind assistance which I have received during this inquiry 
from several gentlemen. Mr. Wild, of the Glodwick Collieries at Oldham, has allowed 
me the free use of his fine collection of specimens, and Mr. Nield, of the same town, 
has been indefatigable in giving me facilities for obtaining others. I have also received 
help from Mr. Whittaker, of Oldham, and from the Eev. W. Higgins, of Huyton. But 
I am mainly indebted to Mr. Butterworth, of Shaw, without whose invaluable coopera- 
tion this investigation could scarcely have been carried on. 
Description of the Plates. 
To facilitate comparative references, each letter of the alphabet up to p is employed 
throughout the following figures to indicate homologous structures. 
a. Fistular medullary cavities. 
c. Primary medullary rays. 
e. Longitudinal internodal canals. 
cj. Vessels of woody wedges. 
i. Nodes. 
t. Infranodal canals. 
n. Nodal diaphragm. 
p. Eoots. 
b. Pith-cells. 
d. Secondary medullary rays. 
f. Woody wedges. 
h. Cortical layers. 
Jc. Internodes. 
m. Branches. 
o. Divergent woody wedges. 
PLATE XXIII. 
Pig. 1. Diagrammatic restoration of part of the stem of a Calamopitus, from the left 
portion of which the bark has been removed exposing the exterior surface of 
the woody zone, and from the right both bark and wood are removed, revealing 
the outer surface of the pith. The branch at m exhibits its medulla (b 1 ), sur- 
rounded by its woody zone, f. 
Fig. 2. Tangential section of a Catamites crossing the node. 
Fig. 3. Portion from fig. 2, a, more highly magnified. 
Fig. 4. Eeticulated vessel of Calamites. 
Fig. 5. Tangential section of part of a woody wedge with barred vessels and medullary rays 
Fig. 6. Transverse section of part of fig. 5. 
