168 Proceedings of the Royal Society of Edinburgh. [® ess - 
us, and from the statement of Mr Carl F. Herlofson, the director of the 
Bunaveneader Whaling Station, that on previous occasions he had noticed 
teeth protruding from the upper jaw of Sperm Whales landed at the station. 
Rare occurrences of projecting teeth have at other times been observed, 
but we are aware of no evidence of their utility, apart from a deduction 
formed by Pouchet and Beauregard from one out of several maxillary 
teeth received from Ponta Delgada in the Azores, and mentioned in a foot- 
note : “ L’une d’elles parait avoir ete saillante en dehors de la muqueuse, ce 
qui arriva, on le sait, quelquefois, et presente a son extremite une legere 
usure.” * 
As there is still some indefiniteness regarding the shape of the head of 
the Sperm Whale, and especially regarding the distance of the mouth behind 
the extremity of the head, a photograph of the specimen bearing the 
functional maxillary teeth is reproduced, showing the head, from the under 
surface, with the lower jaw open (fig. 3). In this are clearly visible the 
mandibular pits in the upper jaw, the grooves in which the maxillary teeth 
lie (though these teeth themselves are, unfortunately, on too small a scale 
to be visible), and an enormous squarely truncated pre-oral rostrum. In 
this last respect the Bunaveneader specimen differs greatly from the 
Inniskea bull sperm figured by Lillie, f in which the tip of the mandible is 
close to the anterior of the head ; and it differs as much from the smooth 
round-muzzled Azores specimens figured from photographs by Pouchet and 
Chaves, who stigmatise as inexact those figures “ representant l’animal avec 
Pextremite de la tete aplatie et comme coupee carrement.” J Those state- 
ments can be correlated with our own observations of square, truncated 
muzzles and receding mouth, only by supposing that there occurs a wide 
range of variation in the proportions and shape of the head parts, but it is 
possible that some differences, as perhaps those between our and the 
Azores specimens (the sexes of the latter are unrecorded), may indicate 
sexual dimorphism. Nevertheless, in each of the seven male Bunaveneader 
examples examined by us there was a distinct pre-oral rostrum similar in 
proportion to that here figured. It projected about a yard in front of the 
tip of the mandible, and was so tough and fibrous in nature that it could 
be cut only with great difficulty. 
* Pouchet et Beauregard, “ Sur un Cachalot echoue a Pile de Re,” Jour, de VAnat. et 
Phys vol. xxvii., 1891, p. 132, f.n. 
t Lillie, “ Observations on the Anatomy and General Biology of some Members of the 
Larger Cetacea,” Proc. Zool. Soc. London , 1910, part 2, p. 788, fig. 78. 
f Pouchet et Chaves, “Des Formes exterieures du Cachalot,” Jour, de VAnat. et Phys., 
vol. xxvi., 1890, p. 270. 
{Issued separately April 22, 1913.) 
