Zoopuyva. | UPPER PALAOZOIC RADIATA. 107 
Genus. STYLASTRAA (Lonsd.) 
Ref—Geol. Russ. p. 619. 
Gen. Char.—Corallum forming large masses, composed of prismatic, easily separable tubes, each having 
a thick, distinct, epithecal wall, marked with vertical costal stria, and transverse rugosities of growth; 
within the external epithecal boundary of each tube, is a narrow vesicular perithecal zone, usually radiated 
obseurely by delicate costal prolongations of the radiating lamelle ; within the perithecal zone, is a circular 
lamelliferous area, or true cell, traversed horizontally by distinct, strong diaphragms, without central axis ; 
radiating lamellze numerous, strong, biplated, of two sizes, not reaching the centre; young, produced as 
four-sided columns, by a rectilinear boundary, parallel to one of the faces of the old prismatic tube. 
STYLASTR#A BASALTIFORMIS (Phill. Sp.) 
Ref. and Syn.—Oyathophyllum basaltiformis Phil. Geol. York. Vol. II. t. 2. f. 21. 
Sp. Ch.—Corallum forming large masses of easily separable prismatic tubes, often ten inches long, 
usually hexagonal, with an average diameter of four lines, or rather less; circular inner area usually three 
lines in diameter, radiated by about twenty-five thick primary lamelle, leaving a clear unradiated central 
space, of rather more than a line in diameter; narrow outer vesicular area, of from two to four rows of 
cells, faintly radiated by delicate costal extensions of the thick primary lamelle, and an equal number of 
intervening secondary lamellz, which barely enter the lamelliferous zone; surface marked with strong, 
irregular, transverse wrinkles of growth, and coarse vertical lamellar striae, averaging six or seven in two 
lines: vertical section, inner area traversed by broad, distinct, nearly flat, subregular, horizontal diaphragms, 
about five in two lines; outer area, of very highly inclined, slightly curved vesicular plates, usually two 
in a row. 
I have seen, in one or two cases, a slight axis-like projection of the middle of a diaphragm, but 
there was nothing of the sort on the diaphragm above or below it. The peculiar mode of forming easily 
separable young square tubes is often observed in this species. 
Position and Locality —Abundant in the carboniferous limestone of Kendal, Westmoreland. 
Genus. SIPHONODENDRON (M7/°Coy). 
Ref —M*Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 127. 
Gen. Char.—Corallum of variously aggregated, branching, cylindrical or elongate-conic stems; young 
branches produced by lateral buds; outer wall thin, lined by two or three rows of small vesicular plates, 
forming a narrow outer vesicular, or perithecal area in both sections, defined by a thin tubular wall; 
terminal cups deep, lined by numerous vertical lamellze, alternately larger and smaller, and having in the 
bottom a small prominent, styliform, compressed axis: vertical section shews a slender, central axis, and 
a series of large conical or dome-shaped transverse diaphragms, occupying the greater part of the width 
of the tube, the convexity upwards forming in this section lines diverging downwards and outwards from 
the axis, till they reach the narrow external cellulose layer on each side: horizontal section shews the small 
axis, surrounded usually by a few thin concentric lines, which are the edges of the conoidal diaphragms 
cut through by the section; from these the vertical lamelle radiated to the circumference, where they are 
connected by the small transverse vesicular plates, forming the narrow external cellular zone. 
I have proposed this genus for a number of corals exceedingly abundant in the mountain limestone, 
but hitherto classed, by Prof. Phillips, Mr Lonsdale, and others, with Lithodendron. This latter genus 
was originally proposed by Schweigger (Beobachtungen, &c. tab. 6) to include, first, the Oculina of Lamark, 
including the type of Blainville’s Dendrophyllia; and secondly, a division, which, allowing the previously 
constituted genus Oculina and the subsequently defined Dendrophyllia to stand for the first division, beecmes 
the real type of his genus, and the four references he gives to Esper’s ‘ Pflanzenthiere’ (L. capitatum 
Sastigiatum, angulosum, cristatum), as examples of this genus are typical examples of the group subse- 
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