62 DR. D. H. SCOTT ON A NEW TYPE OF MEDULLOSEZ 
In spite of the differences to wbich attention has been called, there is no doubt of the 
close affinity of Rachiopteris Williamsoni with Sutcliffia insignis, and I have little 
hesitation in placing the former in the genus Sw/cliffie, under the name Suwtcliffia 
JVilliamsoni. 
Summary. 
Sutcliffia insignis was a large stem, probably of considerable height, the surface 
clothed by spirally arranged leaf-bases of great size relative to the stem. 
The vascular system of the stem consisted of a single main stele with solid wood 
(protostele), from which meristeles or subsidiary steles were given off. 
The meristeles divided up, the branches of adjacent meristeles sometimes fusing with 
one another, and gave rise to the numerous leaf-trace bundles. 
The xylem in all parts of the vascular system was exarch, and consisted of tracheides 
interspersed with xylem-parenchyma. The walls of the larger tracheides bore multi- 
seriate bordered pits. The formation of secondary wood and bast had begun to a small 
extent around the stele and some of the meristeles. The phloem of the stele and 
meristeles consisted of strands of narrow elements (sieve-tubes) embedded in parenchyma. 
In the bundles of the leaf-bases and petioles numerous large phloem-elements, probably 
of the nature of sieve-tubes, were present. The pericycle and cortex were traversed by 
secretory canals. The leaf-bases and detached petioles were of similar structure, the 
hypoderma having radially arranged sclerotic bands as in Myeloxylon; other sclerotic 
strands traversed the ground-tissue. The foliar bundles, which were present in great 
numbers in the petiole, were in all cases of concentric structure. 
Diagnosis. 
SUTCLIFFIA, gen. nov. 
Surface of the stem clothed by the large, spirally-arranged leaf-bases; vascular 
system of stem consisting of a single protostele, giving off meristeles, which branch and 
undergo fusion, ultimately giving rise to the leaf-traces. 
Xylem exarch. Tracheides mostly with multiseriate bordered pits. Leaf-bases and 
petioles with the general organization of Myeloxylon, but all vascular bundles concentric. 
SUTCLIFFIA INSIGNIS, sp. nov. 
Petiolar bundles approximately circular in transverse section, each of them invested 
by a ring or horseshoe of sclerenchymatous strands; phloem containing numerous large 
elements, forming a conspicuous circle round the bundle, and probably representing the 
sieve-tubes. 
Stem, in the one specimen known, 12x65 em. in diameter. Detached petioles 
sometimes exceeding 12 cm. in diameter. 
Localities. Shore-Littleborough and Colne, Lancashire. 
Horizon. Lower Coal-Measures. 
I have given above the specific characters which may serve to distinguish Sutelifia 
insignis from S. Williansoni (Seward). 
