66 CETACEA. 



M. 3559. Cast of the cranial rostrum, with a fragment of the inter- 

 orbital region. The original is in the collection of 

 Dr. Bree of Colchester, and was dredged in the North 

 Sea, having been derived from the Red Crag. 



Made in the Museum. 



44176. The cranial rostrum, with a fragment of the interorhital 

 region ; from the Red Crag of Suffolk. Purchased, 1873. 



39459. The imperfect anterior extremity of the cranial rostrum of 

 a large individual ; from the Red Crag of Suffolk. 



Purchased, 1865. 



39509. The cranial rostrum ; from the Antwerp Crag. 



Purchased, 1865. 



33459. The centrum of a first caudal vertebra which may belong 

 to this species ; probably from the Coralline Crag. This 

 specimen is somewhat larger than the first caudal of Meso- 

 plodon australis, but agrees very closely in character. 



Layton Collection. Purchased, 1858. 



M. 3535. Cast of the left periotic, provisionally referred to this 

 species. The original was obtained from the Red Crag of 

 Woodbridge, Suffolk, and is preserved in the Museum of 

 Practical Geology, Jermyn Street ; it is described and 

 figured by the present writer in the ' Quart. Journ. Geol. 

 Soc.' vol. xliii. p. 14, pi. ii. fig. 7. It has lost the accessory 

 ossicle on the posterior half of the tympanic aspect ; and is 

 intermediate in size and structure between the periotics 

 of Hyperoodon and Mesoplodon, although nearer in respect 

 of structure to the latter. The specimen approaches 

 Hyperoodon in the relative shortness of the posterior ex- 

 tremity, the strong development of the median articular 

 ridge on the tympanic aspect of the same portion, and the 

 large size of the cavity for the accessory ossicle; the 

 anterior articular fossette for the tympanic is also less 

 markedly concave than in Mesoplodon. The specimen 

 accords well in size with the present species, to which it 

 is referred as being the one of most common occurrence in 

 the Crag. Made in the Museum, 1886. 



