LOWER PALAZXOZOIC RADIATA. 37 
Zoopuyva.| 
tubes generally rather distant from each other, forming circular cells on the surface, the interval being of 
a fine cellular texture, having an obscure horizontal arrangement, and sometimes shewing radiating lines, or 
costal prolongations of the lamellze on the surface, but having no polygonal epithecal boundaries between 
the exotheca of the individual cells; a thin epitheca at base of the entire compound mass. 
The buds or young tubes seem to arise from the interstitial cellalar substance (as in Anthophyllum, 
Ehrenb. not of Goldfuss, &c.) wherever the distance becomes great between any two cells, but the young 
tubes do not seem traceable into the old. This genus is perhaps scarcely distinguishable from the more 
recent Fascicularia (Lam. 1812 = Stylina, Lam. 1816), except by the ccenenchyme forming a uniform 
vesicular mass, instead of dense, separated, transverse lamellee. 
SARCINULA ORGANUM (Linn. Sp.) 
Ref. and Syn.—Madrepora organum Linn. Amoen. Acad. t. at p. 312, f.6 and 1. Sareinula organum 
(His. Leth. Suec. t. 27. f. 8. id. Gold. Pet. Germ. t. 24. f. 10). 
Sp. Ch.—Corallum forming large irregular masses of subparallel, nearly vertical, cylindrical, thick- 
walled tubes ; averaging slightly more than one and half lines in diameter, and varying slightly in distance, 
but usually a little more than their diameter apart; upper surface with the tubes forming deep cylindrical 
cells, each surrounded by a slightly concave outer area, inclining a little upwards and outwards, so as to 
form an angular ridge, forming polygonal boundaries between the cells, each centre surrounded by twenty- 
four to twenty-six thick, equal, radiating sulci; young columns interpolated: horizontal section shews the 
thick circular walls of the tubular centres, surrounded by an obscure radiation and vesicular structure, 
but no polygonal boundaries between the cells: vertical section shews the strong walls of the vertical tubes 
and the interior of the latter, divided by irregularly shaped, strong, transverse diaphragms, averaging four 
in a space equal to the diameter of the tube; intertubular spaces occupied by strong upward-arched 
transverse plates, rather more numerous than the diaphragms. 
It is remarkable that this long described coral should not have been recognized before in Great 
Britain. It varies greatly according to the state of preservation, one of the most common weathered 
conditions shewing the tubes projecting from the compact mass of the matrix, as long, separated, slightly 
fringed, cylindrical, quill-like columns. 
Position and Locality—Extremely common in the Coniston limestone of Coniston Water-Head, 
Laneashire ; Sunny Brow, near Coniston; High Haume, Dalton in Furness, Lancashire ; and Coniston 
limestone, Long Sleddale, Westmoreland; Applethwaite Common, Westmoreland. 
2nd Subfamily. ASTR/AIN A. 
Lamellz with lobed or denticulated edges, costze spinulose; axis usually reticulated, rarely lamellar, 
never styliform. 
This subfamily contains sectional groups similar to those of the Husmiline, the only Paleozoic genera 
probably entering the subfamily, are Arachnophyllum and Palastrwa, which should probably be placed near 
Acanthastrwa and Synastrea. 
Genus. ARACHNOPHYLLUM (Dana). 
Gen. Char.—Corallum forming large irregular incrusting* masses, having on the upper surface obtusely 
defined polygonal stars, each with a depressed flattened centre in which the radiating lamelle meet ; 
Sarcinula organum of Lamarck, “Cette espéce différe beaucoup du Madrepora organum de Linné, qui est un fossile des ter- 
rains de transition, et auquel elle avait été rapportée par Lamarck. C’est ce dernier polypier qui forme le genre Sarcinula 
pour M. Dana et M. M°Coy.” Surely Mr Dana and myself have here done what was right according to strict rules of 
nomenclature; Lamarck made a blunder in identifying a recent coral with the Silurian one of the Swedish naturalists, and 
no one should follow him, now that the distinctions are known. That the Sarcinula organum (Linn.) is the true type of the 
genus Sarcinula, is further proved by the fact, that the other species of Sarcinula, as defined by Edwards and Haime, noted 
by Lamarck, were placed by him in the genus Caryophyllia. 
* A specimen which had incrusted a fragment of Cyathophyllum misled me formerly as to the septate structure of the centres. 
