R. B. Neidon — On the Genus Leveillia. 205 



(Porcellia) was also included in the family. In 1864, Prof. James 

 Hall ^ described Tremanotus, a new Bellerophontoid genus, from 

 the Niagara Limestone of Illinois, which possessed a regular series 

 of siphonal openings on the dorsal region of the shell instead of the 

 uninterrupted band. This discovery led to some valuable observations 

 by the late Mr. F. B. Meek,^ in 1866, who, grasping the importance 

 of this unusual character in Prof. Hall's genus, looked upon it as 

 the chief link of evidence required to prove the Prosobranchiate 

 affinities of BelleropJion, and the desirability of associating it with 

 the fissured shells of that group in close proximity to the Haliotidas, 

 Fissurellidse, and the Pleurotomariidae. It is satisfactory to note 

 that Meek's decision in this matter is at last being recognized with 

 favour, having been adopted by Prof. Karl Zittel ^ in 1882, Mr. 

 E. Etheridge, jun.,* in 1882, De Koninck ^ in 1883, Dr. Paul 

 Fischer ^ in 1885, and lastly by Messrs. Nicholson and Lydekker ^ 

 in 1889. 



Distribution of Leveillia. — Devonian, Carboniferous, and Triassic 

 Eocks of various localities in England, Ireland, Scotland, Belgium, 

 France, Germany, Russia, America and Australia. 



The Triassic species are peculiar to Hallstatt and St. Cassian. 



Leveillia (Porcellia) Puzo,^ C. Leveille, 1835. 



Mem. Soc. Geol. France, 1835, vol. ii. pi. xi. figs. 10, 11, p. 39. 



Goniatites inter costalis, J. Phillips, 1836. 



Illust. Geol. Yorkshii-e, Part 2, Mountain Limest. District, 1836, pi. 20, 



figs. 61, 62, p. 237. 



Porcellia Puzo, L. G. de Koninck, 1843. 



Desc. Anim. Foss. Terr. Garb. Belgique, 1843, pi. 28, fig. 1, p. 359. 

 Faune Calc. Garb. Belgique, 1883, pi. 35, figs. 26-28, p. 116. 



There is nothing to add to the characters of this type as originally 

 defined by Leveille, and which have been further added to by 

 De Koninck. A notice of the species here is necessitated by the 

 introduction of Phillips' Goniatites intercostalis into its synonymy 

 for the first time. The brief description, as given by Phillips of 

 this species stands thus : " Discoid, whorls costato-tuberculated on the 

 sides, round on the back, with spiral intercostal striee," and this is 

 accompanied by two figures, one showing a side view with its nodu- 

 lated whorls, the other exhibiting the size and shape of the aperture, 

 both figures being taken from different specimens preserved in the 

 " Gilbertson Collection," now arranged as one of the separate type 



1 Eighteenth Eept. Eeg. Univ. Ne^w York, 1864, p. 347 ; Twentieth Eept. 1867, 

 pi. XV. figs. 23, 24. 



- Note on the Afiinities of the Bellerophontidse, Proc. Chicago Acad. Sciences, 

 1866, vol. i. p. 9. 



3 Handb. Palteontologie, 1882, p. 183. 



* Proc. Roy. Phys. Soc. Edinburgh, 1882, vol. vii. part i. p. 73. 

 ^ loc. cit. p. 119. 



6 Man. Gonchyliologie, 1885, p. 852. 



■^ Man. Palaeontology, 1889, ed. 3, vol. i. p. 767. 



* For a fuller synonymy of this species the student is referred to De Koninck's 

 "works as here quoted. 



