38 BRITISH PALAOZOIC FOSSILS. [Zoopuyra. 
radiating lamelle fine, granulose, perforated, strongly marked about the depressed centre, their costal exten- 
sions becoming very fine towards the margin, where those of adjacent stars are often continuous; buds 
marginal ; vertical section shewing a sub-uniform small vesicular structure, arranged in transverse undula- 
tions corresponding to the form of the cells, the curve directed downwards under the centres and upwards 
between them; no defining walls to the centre or between the stars; centre marked by a few vertical 
strize resulting from the twisted edges of the vertical lamellze. 
This genus differs from Sarcinula in wanting the distinct-walled, septate, tubular centre ; from the 
compound Strephodes it differs in the absence of solid boundary walls to the cells in both sections; and 
from Acervularia by its lateral buds, and want of solid boundaries to the centre and to the stars in 
the sections. 
ARACHNOPHYLLUM Typus (M°Coy). PI. 1. B. fig. 27. 
Syn. and Ref—M°Coy, Ann. Nat. Hist. 2nd Series, Vol. VI. p. 278. 
Acervularia Baltica (Schw.) Lonsd. pars. Sil. Syst. t. 16. f. 84. (not of Schweigger). 
Sp. Ch.—Corallum forming thick irregular enveloping masses; upper surface undulated, covered with 
large shallow polygonal stars, defined by very obtusely angular ridges; the centres averaging seven or eight 
lines apart, circular, depressed, rather more than one-third the diameter of the star, radiated with about 
thirty-three strong, granulose, sub-alternate, lamellee, half of which reach the flattened centre where they 
are irregularly united and slightly twisted; on the outer inclined area of each star each of the lamelle 
becomes much thinner and more faintly marked, branching di- or tri-chotomously once or twice, and often 
waving in a variable manner before reaching the boundary, over which they frequently pass into the 
adjoining stars; vertical section shewing a few delicate vertical striz under the centres of the stars (edges 
of the twisted vertical lamellee), and a nearly uniform small vesicular tissue, the cells of irregularly unequal 
size, passing from star to star, with a few irregular dense bands nearly coinciding in curvature with the 
form of the cells: average of larger cells two to three in one line. 
That this is one of the fossils figured by Mr Lonsdale in the “Silurian System,” as the Acervularia 
Baltica of Schweigger, | have little doubt, but neither the particular figure which I refer to above, nor the 
others which that writer has given under the same name in that work, have any specific relation to the true 
Acervularia Baltica of Schweigger, who avows that name to be only a synonym of the A. ananas (Linn. Sp.) 
referring to the original figure, We. in the Amenitates Academicw of Linné, representing a coral which 
has a distinct-walled tubular centre, from which the groups of young are developed, solid walls between 
the cells, &e. (See Acervularia ananas). The lateral disk buds are often seen in this curious coral. 
Position and Locality—W enlock limestone, near Aymestry, Herefordshire. 
Explanation of Figures —Plate 1. B. fig. 27. Natural size from Aymestry, portion of large mass.— 
Fig. 27a. Portion of ditto magnified three diameters, shewing the form of the cup, with the strong 
lamellie lining the depressed centre, becoming abruptly thinner, more numerous by branching, and flexuous 
as they pass irregularly into those of the adjoining stars; the vertical section in lower part shewing the 
uniform vesicular tissue of the whole mass, without divisional walls to the cells; the few vertical lines under 
the centre are divided edges of some of the lamelle. 
6th Family. TURBINOLID. 
Corallum usually simple, never fissiparous, sometimes increasing by lateral buds; radiating lamellze 
strong, simple, usually granulated on the sides, no connecting vesicular plates or processes ; epitheca thin, 
usually imperforate, surface usually marked with lamellar sulci; no ccenenchyme in the compound forms. 
Subfamilies:—1, Cyathine; 2, Turbinoline ; 3, Eupsammine. 
