190 PERMIAN FOSSILS. 



obscmus. From an examination of the original specimen belonging to Mr. Binney, of 

 the unnamed fossil represented in the 'Transactions of the Manchester Geological 

 Society,' vol. i, pi. 6, fig. 18, I have little doubt of its belonging to this species. I 

 cannot speak so confidently of the specimens represented by figs. 30 and 31, under 

 the names of Jxinus parvus and Aaoinus undatus, though I have a strong suspicion of 

 their being the same. By tracing the lines of growth on Mr. Binney's specimen of 

 the so-called Axinus undatus, I cannot perceive any flexure corresponding to the one 

 in the ventral margin ; on the contrary, the fossil appears to be broken where the 

 flexure occurs. 



Schizodus ohscurus occurs very abundantly at Garforth Cliff Quarry near Leeds ; 

 Woodhall, Yorkshire ; Stubbs Hill near Doncaster ; and Nosterfleld. Mr. Binney has 

 collected it at Kirkby Woodhouse, Notts ; Bolsover ; near Elmsall, Yorkshire ; Bedford, 

 Atherton, Monton, Patricroft, and Newtown in Lancashire. It probably occurs at 

 Ferrybridge ; as Professor Phillips found a fossil there, which is supposed to be the 

 present species. (Phil. Mag., New Series, vol. iv, p. 401, 1828.) 



ScHizoDUS ROTUNDATUS, Bfown. Plate XV, fig. 30. 



Axinus eotundatus, Brown. Trans. Manch. Geol. Soc, vol. i. p. 31, pi. vi, fig. 29, 1841 . 

 (?) — puciLLUS (young), Brown. Op. cit., vol. i, p. 31, pi. vi, fig. 32. 

 (?) LuciNA MINIMA ,, Op. cit., vol. i, p. 32, pi. vi, fig. 33. 



Last three Synonyms „ Brown, Fossil Conchology, pi. Ixxix, figs. 1, 2, 3, 



10, 11, 12, 1843. 

 Idem. „ Morris, Catalogue, p. 80, 1843. 



Idem. „ De Verneuil, Bull. Soc. Geol. de France, 2°"serie, 



vol. i, pp. 31, 32, 1844. 

 Idem. „ Geol. Russ., vol. i, p. 224, 1845. 



Idem. „ Tennant, Strat. List, p. 88, 1847. 



(?) ScHizoDUS ScHLOTHEiMi, Geinitz. Versteinerungen, pi. iii, fig. 33, 1848. 



Diagnosis. — " Shell nearly orbicular ; umbones almost central, acute, and remote ; 

 surface smooth. Length upwards of three eighths of an inch ; breadth nearly half an 

 inch." ' (Brown.) 



This appears to me to be the only real species which Captain Brown has described ; 

 but it is much to be regretted that the original specimen is so badly preserved, that I 

 am not able to speak with sufficient confidence on this point. By tracing the lines of 

 growth, its posterior half is apparently shorter, and more rounded than in Sc/iizodus 

 ohscurus, or any other congeneric species, with, perhaps, the exception of 8chi%odus 

 Bossicus, which appears to resemble it very closely. Captain Brown is undoubtedly 

 wrong in describing it as being smooth ; as Mr. Binney's specimen is distinctly threaded 

 parallel to the margin. It seems to have had rather thick valves. 



ScUzodus rotundatus was found by Mr. Binney in the Permian Marls at Newtown, 

 near Manchester. 



1 Transactions of the Geological Society of Manchester, vol. 1, p. 31. 



