122 PERMIAN FOSSILS. 



CamaropJioria multiplicata is a very local species, occurring chiefly at Humbleton 

 Quarry, in the Shell-limestone, where it is not very common. I have found a few 

 specimens in the same formation at Dalton-le-Dale. It does not appear to have been 

 discovered anywhere in the Permian rocks of Germany (unless at Ilmenau, vide Gsea 

 von Sachsen, p. 96) or Russia. 



Family Spiriferid^, King, 1846, 

 Delthykid^ {partim), Phillips, 1841. 



Diagnosis. — " The oral arms very largely developed, and supported the whole of 

 their length by a thin, shelly (?), or cartilaginous (?), spirally twisted plate." (Gray.)^ 



Mr. J. Sowerby, in 1815, was the first to separate the shells belonging to this family 

 from the Terebratulce under the name of Spirifer. The institution of Trigonotreta by 

 Koenig was the next step. Fischer de Waldheim shortly afterwards proposed the genus 

 Choristites. Dalman, in 1827, followed in the same track by forming Cgrtia, Atrypa, 

 and BeWiyris. Professor Phillips, in 1841, provisionally proposed the genus Cleiothyris. 

 M'Coy, in 1844, instituted the genera Athyris, Brachythyris, Martinia, Beticularia, and 

 ActinoconcJius. And more recently M. A. d'Orbigny has indicated Spiriferina, Spirigerina, 

 and Spirigera. It will shortly be seen that most of these genera are synonymous. 



The double spiral apophysary system, found in all the genera of this family, 

 constitutes its principal distinctive character. This view was first published, I believe, 

 by myself in 1846, when stating that " the spiral form of the labial processes, their 

 immobility, and their spirally folded supports, are characters which eminently 

 distinguish Spiriferidcs from every other palliobranchiate family."^ 



Previously to the publication of the researches of Professor M^Coy,^ extremely 

 vague ideas were entertained as to the use of the spiral appendages ; but, in accordance 

 with the views of this author, all palaeontologists are now of opinion that they formed 

 the supports of the labial appendages of the Mollusk. Mr. T. Davidson has also 

 contributed to throw some important light on these structures, as existing in the 

 Jurassic Spiriferida ;* and from his late communications to me, I have been put in 

 possession of the important fact, that the two crura of the spirals in the fossils last 

 noticed are connected with each other in the centre of the shell.* It will readily occur 

 to the reader that the homologues of these crura (i. e. the crura of the loop) in 

 TerebratulidcB are projecting and free (vide PI. XX, figs. 11 and \2 E). Had the spirals 

 themselves been thus conjoined, as is the case with the loop in Terebratula and 



' Annals and Mag. of Nat. Hist., 2d series, vol. ii, p. 437. 

 2 Idem, vol. xviii, p. 32. 



^ Vide Synopsis of the Carboniferous Fossils of Ireland, pp. 127-8. 

 * Vide London Geological Journal, vol. i, pp. 110-11, pi. xviii, figs. 1, 2, 3. 



^ Figures illustrating this character will be published by Mr. T. Davidson, in his Monograph of Oolitic 

 and Liassic Brachiopoda, which he is preparing for the Palseontographical Society. 



