Zoopuyra.| UPPER PALAZOZOIC RADIATA. - 109 
SIPHONODENDRON SEXDECIMALE (Phill. Sp.) 
Ref. and Syn.—Lithodendron id. Phil. Geol. York. t. 2. f. 11, 18. 
Sp. Ch.—Corallum forming loosely branched masses; cell-tubes slightly flexuous, subparallel, averaging 
slightly more than one line in diameter, and usually rather less than their diameter apart, branching at 
an acute angle, the branches attaining their fuli diameter at about four lines long; outer wall very thick, 
smooth, with faint transverse lines of growth, without distinct costal strize; axis strong, solid, persistent ; 
transverse diaphragms nearly horizontal, strong, three interdiaphragmatal spaces in one line; radiating 
lamellee of moderate thickness, sixteen long, reaching quite to the axis, or a few occasionally uniting 
branch-wise with their neighbours; an equal number of very short marginal ones, one between each pair 
of primary. 
The very small size of the branches, and small number of the lamellze, easily distinguish this rare 
species from its congeners. 
Position and Locality—Not uncommon in the carboniferous limestone of Kendal, Westmoreland ; impure 
carboniferous limestone of Lowick, Northumberland; also at Burdiehouse ; and carboniferous limestone of 
Derbyshire. 
Family. ASTREIDZ. See page 36. 
Subfamily. EUSMILIN. See page 36. 
Genus. CYATHAXONIA. See page 36. 
CYATHAXONIA CORNU (Mich.) 
Ref.—Michelin, Icon. Zooph. t. 59. f. 9. 
Sp. Ch.—Corallum very small, slightly curved when young, nearly straight when old, the adult diameter 
of about three and half lines, is reached at about six lines from the apex; sometimes an inch in length 
with the same diameter; axis prominent, thick, solid, cylindrical, about one fourth the diameter of the 
tube ; radiating lamellze appearing in small terminal cups as thirty-five or thirty-six alternately larger and 
smaller lamellee, which unite in pairs near the axis: horizontal section of larger specimens shew twenty-four 
radiating lamelle, extending from the axis a short way, and then splitting into a pair of slender ones, 
extending to the walls; no connecting vesicular plates; external surface with distinct, obtuse, close 
vertical strize (about five in one line) branching not unfrequently; no transverse vesicular plates. 
I have compared the specimens described with one from the original locality of Tournay, and find 
the coincidence exact. 
Position and Locality—Rare in the carboniferous limestone of Derbyshire ; and Kendal, Westmoreland. 
CYATHAXONIA CosTATA (J/‘Coy). Pl. 3. C. fig. 2. 
Ref.—M°Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 6. 
Sp. Ch.—Elongate-conic, generally about one inch long and half an inch in diameter at the cup, which is 
circular and horizontal ; surface irregularly wrinkled transversely, and marked longitudinally with remarkably, 
thick, strong, sharply-defined strize, about seven in one-fourth of an inch; central solid axis very thick 
(often one line in diameter), and from it twenty-five thick, wedge-like, vertical lamelle, radiate to the walls ; 
transverse versicular plates connecting the lamellz exceedingly delicate ; in the sections the vertical lamellze are 
seen to dichotomize upwards, and the large curved plates of the loose vesicular structure incline upwards and 
inwards towards the axis. 
