108 PISCES. 



Genus NOTIDANUS, Cuvier. 



The occurrence of the genus Notidanus in the English Crag 

 seems to have been first recorded by Mr. H. B. Woodward in the 

 Survey Memoir (Geology of Norwich, p. 54, 1882), who noted 

 a specimen from the Norwich Crag of Thorpe, in the collection of 

 Mr. R. Fitch. The small size of the specimen unfortunately led 

 to its being named N. microdon ; but a closer examination, recently 

 made, leads me to think that my former determination was in- 

 correct, and that it cannot be referred to the Cretaceous species ; 

 possibly it may be a small example of the form now to be 

 noticed. 



NJOTIDANUS GIGAS, SISMONDA. 



PLATE IX., FIG. 18. 



When Mr. A. Smith Woodward (Geol. Mag., Dec. 3., Vol. III., 

 p. 205, 1886) published his revision of the genus Notidanus he 

 noted three species as occurring in the English Crag, N. primi- 

 genius, N. gigas, and N. Mencghini. I suggested at the time that 

 there was not sufficient grounds for separating the two species last 

 named, and in my MS. prepared for the present memoir I 

 wrote : 



" With regard to Notidanus Meneghini, Lawley, I fail to see 

 any good reason for making it distinct from N. gigas, Linn. A 

 comparison of the figures given by Sismonda of N. gigas (Mem. R. 

 Ace. Sci. Torino, Ser. 2, Vol. XIX., p. 460, Fig. 13), by Lawley 

 of the same species and of N. Meneghini (Atti Soc. Toscana, Vol. 

 Ill, Plate i, Fig. 6, and Plate ii, Fig. 4), and by Smith Woodward of 

 these same species (Geol. Mag., Dec. 3, Vol. III., pp. 255, 256), 

 seems to show smaller differences between them than have been 

 accepted as variations of N. primigenius (compare also Agassiz, 

 Poiss. Foss., Vol. III., Plate 27, Fig. 16, Lawley, loc. cit. Plate i, 

 Fig. 1, Smith Woodward, loc. cit. Plate vi, Fig. 22). Such 

 being the case N. Meneghiniis regarded as a synonym of N. gigas; 

 indeed, it seems not improbable that both these species may 

 eventually prove to be varieties of Agassiz's N. primigenius" 



I am glad to find that Mr. Smith Woodward (Cat. Foss. Fishes, 

 B. M., Parti, pp. 164, 165) is now practically of the same opinion, 

 for he only acknowledges one species in the English Crags, 

 N. gigas, and keeps the name of N. primigenius for the Eocene 

 forms. 



Notidanus gigas has been found in the Nodule-bed of the Red 

 Crag at Woodbridge, Butley, Felixstow, and other localities in 

 Suffolk ; and examples are to be seen in the British Museum, 

 and Museum of Practical Geology, as well as in the Museums 

 at York and Ipswich. The species likewise occurs in the Plio- 

 cene of Tuscany. 



