442 
The Coal of Australia. 
cannot do better than as I have proposed. I may then briefly 
characterize the genus and species as follows:— 
Phyllotheca. 
Gen. Char. Stem slender, jointed, simple or branched; branches 
springing from above the joints, not arranged in the same 
plane; surface smooth or longitudinally sulcated ; articulations 
surrounded by sheaths, the free edge of which terminates 
in long narrow leaves, having a more or less distinct midrib. 
Inflorescence arranged in whorls near the extremity of certain 
branches 
I have only too add to the above characters, that the ridges of 
the sulcated stems do not alternate at the joints in the regular 
manner of Calamites, nor is there any trace of the peculiar tu¬ 
bercles so generally seen in that genus (an additional proof, if 
such were wanting, that Brongniart's original explanation of 
those tubercles being connected with the vascular system of the 
sheath is not the correct one, for here we have enormously de¬ 
veloped sheaths and no tubercles). The verticillate whorls of 
leaves, whenever I have seen them perfectly expanded, seemed 
always elliptical as in Annularia, the leaves of two opposite points 
of the circumference being considerably longer than the rest. 
The genus is distinct from Annularia by the great developement 
of the sheath or connected base of the leaves, and by the branches 
being inconstant, and when present, not being arranged in pairs 
in the same plane. 
Phyllotheca australis (Br.) 
Sp. Char. Stem simple, smooth or slightly striated ; sheaths 
tight, shorter than the internodes, terminated by narrow 
leaves, double the length of the sheaths, without distinct mid¬ 
rib. (Condensed from Br.) 
Phyllotheca ramosa (M’Coy). 
Sp. Char. Stem branched, smooth or slightly striated ; sheaths 
half the length of the internodes; leaves thin, linear, flat, 
twice to three times the length of the sheath, with a very fine 
indistinct midrib. 
This beautiful plant has the branches weeping or hanging 
