210 A. Smith Woodward — On the Genus Notidanus. 



the ordinary lateral teeth, the principal cone is destitute of serrations 

 on its anterior border, and is followed by three (or sometimes four) 

 much smaller cones. These teeth chiefly differ from JV. Munsteri 

 in the wider interspaces between the successive cones. They are 

 also somewhat larger, and the apex of each cone occasionally ex- 

 hibits a slightly hooked appearance. 



Other teeth of the type just described are met with in the Upper 

 Corallian beds of Schnaitheim, Wiirtemberg, and were originally 

 figured by Quenstedt (loc. cit.) under the name of N. Miinsteri. 

 Wagner makes a brief allusion to these at the end of his description 

 of N. eximius, and hints that they may possibly belong to his newly 

 determined species. The National Collection contains a good series 

 of specimens from the same deposit, which appear to leave no doubt 

 of the correctness of this identification, and three of these form the 

 subjects of Figs. 3-5. The teeth exhibit considerable variation in 

 size — from one to two centimetres in length — and this may be due 

 not only to age, but also to differences corresponding to the various 

 parts of the jaw. All, however, are characterized by wider inter- 

 spaces between the cones than is the case in N. Miinsteri. In teeth 

 that are probably from the front region of the mandible (Figs. 3, 4), 

 the principal cone is relatively longer and less oblique than in those 

 further back ; while in anterior teeth of the upper jaw, the principal 

 cone is still more prominent and placed erect upon the base. Fig. 5 

 represents one of the latter type, and the original of fig. 34, pi. 96, 

 in Quenstedt's " Jura," is probably another from nearly the same 

 situation. Of lower teeth, the other illustrations of Quenstedt are 

 evidently characteristic examples, and Fig. 3 is a drawing of the 

 largest tooth in the British Museum Collection ; this specimen — like 

 two others, Nos. 22489 and p. 4708 — is remarkable on account of the 

 oblique abrasion of the apex of the principal cone, which appears to 

 have been produced during the life of the animal. The same figure 

 also shows a slight crimping at the lower part of the anterior edge 

 of the tooth; and fig. 33, pi. 96, of Quenstedt's "Jura," likewise 

 exhibits this feature upon a greater extent of the border, but there is 

 no definite denticulation. 



It is interesting to add that Wagner further records a single tooth 

 of N. eximius from Daiting, and another from the Lithographic Stone 

 of Nusplingen, Swabia. 



The upper tooth shown in Fig. 6 was also obtained from the 

 Schnaitheim beds, but it appears scarcely referable to iV. eximius, 

 and must remain at present specifically undetermined. 



4. N. Wagneri, Agassiz, sp. 



1843. Aellopos Wagneri, L. Agassiz, Rech. Poiss. Foss." vol. iii. p. 233. 

 1861. Notidanus Wagneri, A. "Wagner, Abh. k. bayer. Akad. d. Wiss. cl. ix. 

 vol. ix. pp. 296-299. 



In the volume of the "Neues Jahrbuch " for 1836, p. 581, Count 

 Minister briefly recorded a Selachian fossil from the Kelheim Litho- 

 graphic Stone under the name of Aellopos elongatus. It exhibited 

 nothing more than the hinder region of the body, and its affinities 



