404 Davis — On the Fossil Fish of the Cretaceous Formations of Scandinavia. 



and for the most part without root. The latter do not present any character 

 which will distinguish them from the median cusp of Otodus appendiculatus, Ag., 

 but are so similar in size and form that there can be no other course but to include 

 them, although without lateral denticles, in the same species. Had they been 

 found dissociated from the undoubted teeth of Otodus they would have been con- 

 sidered as teeth of Oxyrhina mantelli, Ag. ; and it may still be possible that more 

 minute investigation in the strata at Faxe will prove that the latter is their proper 

 location. The peculiar nature of the matrix, and the manner in which it is 

 cemented together, renders the extraction of the fish-teeth in a perfect condition 

 difficult ; and the lateral portions, as well as the base of the tooth, are very likely to 

 be broken away unless especial care is exercised.* Specimens to which the 

 matrix is still attached, in nearly every instance exhibit one or both the lateral 

 denticles in situ ; but it is easy to conceive that if the tooth were extracted from 

 the limestone the median large crown would be broken off without the lateral 

 cones and base. If the teeth have been collected by operatives unskilled in this 

 branch of palaeontology, they would probably not exercise the care necessary 

 to obtain the sj^ecimens perfect, and this may account for their present 

 condition. 



The teeth from Oretorp are smaller in size than those from the remaining 

 localities, and in a very large proportion of them the root is broken off, the 

 median cone alone remaining. A few, however, are more perfect, and the root 

 and lateral denticles are preserved. 



Sauvage (" Biblioth. des Hautes Etudes," vol. v., p. 27) doubts whether all the 

 teeth figured by Agassiz (" Poiss. Foss.," vol. iii., pi. xxxii., figs. 1-25) should be 

 included in the same species, and considers that several species are confounded 

 together. Agassiz himself appears to have held the same opinion, and states that 

 among the number of teeth figured there are several which differ from each other 

 more than certain species which have been described as distinct. The teeth 

 represented by figs. 19—25 were probably a distinct species ; and doubt was 

 expressed as to whether figs. 17 and 18 were not also different. If fig. 7 be 

 eliminated along with fig. 9, the latter being possessed of two pairs of lateral 

 denticles, and the former being more of the form of Odontaspis than that of 

 Otodus, the remaining figures seem to possess closely related characters; and, 

 when so curtailed, the larger number of specimens from the Swedish Cretaceous 

 system falls naturally into association with this species. Mr. A. Smith Woodward 

 records the occurrence of a tooth resembling the original of fig. 7 (Agassiz, torn, 

 cit.) associated with a group of about twenty -five others in a block of chalk from 



* The three specimens on the tablet in the collection of the Zoological Museum, No. 305, may be referred 

 to as exhibiting the character here indicated. 



