604 
APPENDIX A. 
(LONSDALE ON CORALS.) 
Astrea emarciata, Fischer, Oryc. Gouvern. de Moscou, pi. 31. fig. 5. p. 154. (Limestone of Tessovo.) 
One of the specimens from which the preceding characters were obtained, had on a label, affixed to it in 
Russia, “ Astrea emarciata ,” and it is therefore presumed that the determination must be correct, though 
the agreement with M. Fischer’s figure was not perfect. It is necessary however to state, that the 
Russian carboniferous coral cannot be considered identical with the original Astrea emarciata from the 
tertiary strata of Grignon, although Lamarck’s descriptive notice is reprinted in the * Oryctographie.’ 
(Anim. sans Vert. 2nd edit. ii. p. 417. No. 29. Oryc. p. 154.) As the specific name appears to be well- 
known in Russia, it is nevertheless deemed correct to retain it, and the generic being altered, it is trusted 
no confusion will arise. 
Between Lithost. emarciatum and the English carboniferous fossil Lithost. floriforme, the following dif- 
ferences may be observed. In transverse sections of the Russian coral, parallel to the upper surface (fig. a), 
the principal vertical lamellae have uniformly a very limited range in the outer zone ; whereas, in si milar 
sections of the British species, they extend almost constantly to the polygonal periphery ; in Lithost. 
emarciatum, again, secondary or intermediate lamellae are nearly wanting, or rudimentary, but in Lithost. 
floriforme they are well-developed, alternating in the outer zone, for the greater part, regularly with the 
primary lamella?, even to the very walls of the columns. Other distinctions consist in the greater 
width of the vesicular plates in the Russian coral, consequent on the small range of the lamellae ; and in 
the number of truncated edges being much less, on account of the plates being less inclined. 
The specimens of Lithost. emarciatum which were examined, consisted of slightly radiating columns of 
variable dimensions, and apparently not separable mechanically. The width of the largest mass was four 
and a half inches, and the altitude three inches. Another specimen presented continuous columns three 
and a half inches in height, with a nearly uniform width of six lines. The greatest observed diameter 
was about nine lines. Vertical sections of many contiguous columns, exhibited, on account of the inter- 
stices between the laminae of the original coral not having been filled with mineral matter, very irregular 
surfaces, formed for the greater part of congeries of curved plates, belonging to the outer zone, variously 
united and inclined upwards ; here and there was likewise a flat, vertical surface, ribbed and crossed by 
edges of fractured vesicular plates, presenting the inner surface of a wall ; and occasionally, but more 
rarely, there was a reticulated semi-cylindrical indentation, flanked on each side by narrow flat perpen- 
dicular planes, which were traversed by nearly horizontal lines, the whole representing different, vertical 
sections of the inner zone ; in some cases again the indentation was replaced by a convex body variously 
traversed by lines, and exhibited an axis half separated from the surrounding structures. A transverse 
section parallel to the upper surface is shown in figure a, and to the under surface in figure b, the triple 
composition of the column being perfectly displayed in both. 
A few remarks must be offered on structural details, 
(1.) Transverse sections of the axis presented very variable characters, but the composition of this 
central area consisted of vertical, waved plates (fig. d ), which converged, more or less regularly, towards 
a medial line (fig. e ), and were united by highly inclined laminae ; the whole being encompassed by a thin 
wall, and forming a persistent elliptical body. No very satisfactory proofs were obtained of any connexion 
between the vertical plates and the lamellae of the surrounding zone ; but some of the attenuated edges of 
the latter abutted against the wall, as well as nearly all the inner extremities of the interstitial, horizontal 
plates (fig. e). The general characters of the interior of the axis, and the mode of union with the lamelli- 
ferous zone, are given in figure (d) ; and the reader is requested to compare the persistent structure with 
the cone-in-cone, or non-persistent composition of the axis of Lithost. mammillare (fig. b, p. 606), as af- 
fording a valuable example of the assistance which this portion of the coral may yield in specific determi- 
nations. A further illustration is noticed in the description of Lithost. astroides (fig. b, p. 607). 
