of 
On Certain Species of Permian Shells said to occur in Car- 
boniferous Rocks. By Professor WILLIAM KING (Queen’s 
College, Galway), Queen’s University in Ireland. 
In the “ Geologist” (vol. ii. p. 19, Jan. 1860), Mr Thomas 
Davidson has appended a foot-note to a paper of his “ On 
Scottish Carboniferous Brachiopoda,” in which he affirms the 
probability that the Carboniferous fauna included the follow- 
ing Permian species,—Dielasma sujlata, Martinia Clanny- 
ana, Spiriferina cristata, Camarophoria Schlotheimi, C. 
globulina, and Lingula Credneri. 
Shortly after the appearance of Mr Davidson’s paper, a 
communication from Mr J. W. Kirkby was read before the 
London Geological Society,* “‘ On the Occurrence of Lingula 
Credneri, Geinitz, in the Coal-Measures of Durham; and on 
the claim of the Permian Rocks to be entitled a System.” In 
this paper, the following species are added to the number 
given by Mr Davidson,— Cythere elongata, C. ornata, Bairdia 
gracilis, and Gyracanthus formosus, With regard to most 
of these—the Entomostraca—Mr Kirkby, however, does not 
refer to them with much confidence, as “ their determinations 
are certainly not so conclusive as those of the Brachiopoda” 
named. In the same paper, Mr Kirkby states,— Through 
the critical and most elaborate researches of Mr Thomas 
Davidson, several of the Permian Brachiopoda have been 
proved to be recurrents from the Carboniferous fauna. 
Some of these had long been suspected by other paleontolo- 
gists to be very closely related to, if not identical with, Car- 
boniferous species.” My share in this work is noticed in a 
foot-note, appended to the last passage, by a reference to the 
“remarks” on one species, viz. Dielasma suflata, in my 
“Monograph of the Permian Fossils of England,” p. 150, 
and in the “ Introduction,” p. xxv., to it; but it will be seen, 
by the following observations on the so-called “ recurrents,’’ 
that I have done a little more than might be concluded from 
simply reading the passage and reference above quoted. 
* Vide “ Quarterly Journal of the Geological Society,” vol. vi. part i, 
p- 412, &c. 
