BIVALVIA. 41 



have been P. Princeps, by Woodward, were, probably, only portions of specimens 

 of this shell which sometimes attains a magnitude of four inches in diameter, a size 

 that might well lead to such an error. 



Our figure is taken from a magnificent specimen found in the beds of the Clyde, 

 and now in the Museum of the Geological Society, presented by James Smith, Esq., 

 of Jordan Hill. 



13. PECTEN VARIUS, Linnceus. 



OSTREA VARIA. Linn. Syst. Nat., ed. 12, p. 1146, No. 199, 1767. 



Poli. Test. Sic., vol. ii, p. 163, t. 28, fig. 10, 1793. 



Don. Brit. Shells, vol. i, pi. 1, fig. 1, 1799. 



Shaw. Nat. Miscel., vol. 23, fig. 993. 



Mawe. Linn. Conch., pi. 14, fig. 4, 1823. 



W. Wood. Ind. Test., p. 50, pi. 10, fig. 31, 1825. 



Burrow. Elem. Conch., p. 144, pi. 9, fig. 2, 1815. 

 PECTEN VAKIUS. Chem. Conch. Cab., vii, p. 331, pi. 66, figs. 633, 634, 1782. 



Crouch. Int. Lam. Conch., p. 12, fig. 4, 1827. 



Brown. Illust. Conch. Gr. Brit., pi. 33, fig. 4, 1827. 



Phil. En. Moll. Sic., vol. i, p. 84, 1836. 



J. Smith. Mem. Wern. Soc., vol. viii, p. 46, 1838. 



G. B. Sow. Conch. Man., fig. 171, 1843. 



Id. Thesaur. Conch., vol. i, p. 76, pi. 19, fig. 214, 218, 1847. 



Thorpe. Brit. Mar. Conch., p. 118, 1844. 



Phil. En. Moll. Sic., vol. ii, p. 58, 1844. 



Lovtn. Ind. Moll. Scand., p. 30, 1846. 



Alder. Cat. Moll. North, and Durh., p. 77, 1848. 



Forb. and Hani. Hist. Brit. Moll., vol. 2, p. 273, pi. 50, fig. 1, 1849. 

 MONOTIS. Dacosta. Brit. Conch., p. 151, pi. 10, figs. 1, 2, 4, 5, 7, 9, 1778. 



Spec. Char. Testa rotundato-ovatd, aquivalvi, (squilaterali, radiatd ; rudiis 26 30, 

 subcompressis, squamoso-scabris ; auricula alterd minima. 



Shell roundedly ovate, equivalve, equilateral, ornamented with 26 30 subcom- 

 pressed rays, which are covered with squamose imbrications ; ears unequal. 



Locality. Clyde Beds. Recent, North Seas, Britain, and Mediterranean. 



This is given by Philippi, as a living species in the Mediterranean, and enumerated 

 by Loven, as an inhabitant of the Coast of Scandinavia ; but it has not yet, that I am 

 aware of, been found in either of the three deposits of the Crag. As it is undoubtedly 

 a fossil, in the Clyde Beds, and found frequently in the upper Tertiaries of Sicily, it 

 may, probably, yet be discovered in the Red or Mammaliferous Crag in our own 

 country. It would not, however, be here introduced simply upon such anticipation, 

 but it is claimed as one of the fossils of our upper Tertiaries. 



