CORALS FROM THE MOUNTAIN LIMESTONE. 191 
Derryloran, in Ireland. According to M. Keyserling, it is also met with in Petschora. 
Specimens are in the collections of the Bristol, Cambridge, and Paris Museums, of 
Professor Phillips of York, &c. 
The name of Lithostrotion was introduced almost a century ago by Luid (1760), 
and applied to a fossil Coral, which must be either the above-described species, or a 
species very nearly allied to it, and presenting the same generical characters. 
Luid’s designation was more recently extended by Fleming to a generical division 
characterised by that Zoologist, in the following terms, ‘“ Corals of aggregate prismatical 
parallel tubes, with simple stellular discs,” (‘ British Animals,’ p. 508.) The genus 
Lithostrotion, thus established in 1828, contained four species, the first of which was 
Luid’s original Lithostrotion, the species No. 4 (L. marginatum, Flem.), although too 
imperfectly characterised to be determinable, evidently belongs to the same generical 
division, but the species No. 3 (L. oblongum), differs from the two preceding ones, and 
belongs to our genus Jsastrea, and the species No. 2 (L. floriforme), is referable to 
neither of these forms, and must be placed in a distinct generical division. It is to this 
last-mentioned genus, (designated recently by Professor M‘Coy, under the name of 
Lonsdaleia,) that Mr. Lonsdale applied the generical name of Lithostrotion, which, according 
to the rules generally followed in zoological nomenclature, evidently belongs to the first, that 
is to say to the group formed by Fleming with Luid’s Lithostrotion and the allied 
species. 
Goldfuss was not acquainted with any well-characterised Zithostrotion, and referred to 
his genus Columnaria, (the typical form of which is C. alveolata,) an almost undeter- 
minable fossil, which he called C. /evis,! and which resembles Luid’s Lithostrotion by its 
generical features. M. Dana, in his elaborate work on Zoophytes, published in 1546, 
very judiciously separates these last-mentioned corals from those which are in reality the 
typical Columnaria of Goldfuss, and which he refers to a new genus, proposed by Mr. Hall, 
under the name of Fuvistella; he was thus led to apply the name of Colwmnaria to Luid’s 
Lithostrotion and to the allied species, that is to say to the genus Lithostrotion of Fleming, 
which must, however, remain distinct from the genus Colwmuaria, of Goldfuss, established 
essentially for the well-characterised fossil described by the German Palzontologist under 
the name of C. alveolata. 
Professor M‘Coy had adopted the natural group designated by Fleming under the 
name of Lithostrotion, and by M. Dana under that of Co/wmnaria, but has given to it the 
new name Vemaphyllum. 
In our opinion the limits of the natural group, so well represented by Luid’s 
Lithostrotion, ought not to be restricted to the corals which constitute compact masses, in 
consequence of the complete lateral coalescence of the corallites, but should also comprise 
those which, having the same structure and the same mode of multiplication, are not so 
closely set and form fasciculate aggregations. Sometimes the two forms are met with not 
1 Petref. Germ., tab. xxiv, fig. 8. 
