166 Proceedings of the Royal Society of Edinburgh. [Sess. 
XV. — On the Occurrence of Functional Teeth in the Upper Jaw of 
the Sperm Whale. By James Ritchie, M.A., D.Sc., Royal Scottish 
Museum; and A. J. H. Edwards, National Museum of Antiquities. 
Communicated by Sir Wm. Turner. (With One Plate.) 
(MS. received February 25, 1913. Read March ] 7, 1913.) 
Writers on mammalian anatomy are united in stating that one of the 
characteristics of the Cetacean family Physeteridm is the presence of 
functional teeth in the lower jaw only. Typical statements are those of 
Flower and Lydekker (1891): “No functional teeth in the upper jaw ”; * * * § 
Beddard (1900) : “ Teeth found in both jaws, but those of lower jaw alone 
functional; often very reduced in number”;-]- Turner (1912): “Functional 
teeth in lower, but not in upper jaw.” j A possible exception is the Pigmy 
Whale, Kogia, in which the upper jaw may altogether lack teeth or may 
possess an anterior rudimentary pair (as in K. simus, Owen) the utility of 
which is a matter of some doubt. 
As regards the Cachalot or Sperm Whale ( Phy.seter macrocephalus), it is 
well known that an indefinite number of rudimentary teeth occur in the 
upper jaw ; but these have been held to be relatively small, embedded in 
the gum so that they do not reach the surface, and necessarily, therefore, 
altogether functionless. We have already published a short note § recording 
the result of an examination of six aged bull Sperm Whales caught by the 
Bunaveneader Whaling Company in the vicinity of Rockall, in one of which 
a row of small teeth was visible in the upper jaw. The teeth projected 
from the gum less than half an inch, and each lay close to one of the 
large indentations into which a tooth of the lower jaw had fitted. It was 
remarked that the exposed portions of the teeth did not resemble the sharp 
tips of the rudimentary maxillary teeth described and figured by Sir 
William Turner, || where out of fifteen examples “ in no specimen was the 
crown polished or worn ” ; that, instead, the crowns were distinctly flattened 
* Flower and Lydekker, An Introduction to the Study of Mammals , Livinq and Extinct. 
London, 1891, p. 247. 
t Beddard, A Book of Whales, London, 1900, p. 182. 
f Turner, The Marine Mammals in the Anatomical Museum of the University of 
Edinburgh, London, 1912, p. 71. 
§ Scottish Naturalist, 1912 (March), p. 65. 
|| Turner, “ The Occurrence of the Sperm Whale or Cachalot in the Shetland Seas,” 
Ann. Scot. Nat. Hist., 1904, p. 6, pi. i. ; and previously in Proc. Boy. Soc. Edinburgh, 1903. 
