.322 MR. E. T. NEWTON ON THE CETACEA 



evidence they were not named, but provisionally left vp'here one of 

 them had already been doubtfully placed, that is, in the genus 

 Balcenoptera. As we now know of two other genera of Whales in 

 the " Forest-bed," Physeter and Balcena, the question arises, may not 

 these vertebrae belong to one of these forms ? Let us take, in the first 

 place, the vertebra from Cromer, belonging to Mr. W. Barker of Bir- 

 mingham, to whom I am indebted for measurements and sketches 

 which enable me to give the following particulars of this largest 

 Whale vertebra with which I am acquainted. This specimen, which 

 has lost all its processes, measures about 16 inches across the 

 terminal face, and about 10§ inches from front to back. There is a 

 pair of surfaces below for the attachment of chevron bones, as well 

 .as evidence of the neural arches above, and at the side are the bases 

 of the broken transverse processes. Prom this it is clear that we 

 are dealing with a caudal vertebra which probably belonged to quite 

 the anterior part of that region. The variations in the proportions 

 of length to width in the vertebrae of the large Whales gives a clue 

 to the genus to which they belong, and judged by this standard 

 Mr. Barker's specimen agrees with the anterior caudal vertebrae of 

 Balcena, as shown in the table of measurements (p. 323). It is 

 quite possible that it belongs to the same species as the cervical 

 vertebrae above described, with Which it will for the present be asso- 

 ciated. 



The second large Cetacean vertebra is in Mr Gunn's collection in 

 the Norwich Museum, and is from the " Forest-bed " of Eacton ; it is 

 almost as large as Mr. Barker's specimen, being nearly 15 inches in 

 diameter. Mr. Gunn has most kindly supplied me with measure- 

 ments and other information concerning this vertebra. The two 

 surfaces from which the neural arch has been broken away are seen 

 on the upper part, and at the sides are the bases of the transverse 

 processes. In the middle of the lower surface there is an irregular 

 thickened projection, which seems to be the characteristic ridge of 

 the Whale's lumbar vertebrae. Neither in form nor in the proportion 

 of length to breadth does this vertebra agree with the lumbar ver- 

 tebrae of either Physeter or Balcena. Its measurements, however, 

 agree fairly well with the lumbar vertebrae of Balcenoptera; and, 

 although the inferior ridge is stronger than in either of the recent 

 skeletons I have been able to examine, it seems highly probable that 

 it belonged to a species of that genus. 



Other Cetacean vertebrae of smaller size have been found in the 

 ■" Forest-bed ; " but with the exception of the two forms already 

 referred to Delphinus (Survey Memoir), their affinities have not been 

 determined. 



The following list includes all the Cetacea at present known to 

 occur in the "Forest-bed": — 



Balsenoptera, sp., from Bacton. 



Balsena biscayensis, from Overstrand. 



Physeter macrocephalus, from Sidestrand. 



Monodon monoceros, from Mundesley. 



Delphinus delphis, from Overstrand. 



sp, (near to D. tursio), from Overstrand. 



