EXTERNAL CHARACTERS 24s 



combined by a ventro-lateral extension of the white splash as streaks backwards. In two whales, both 

 females, the white areas were absent from the ventral surface and confined to a partially white lower 

 jaw. This character, a lower jaw half-white or more downwards from the alveolar margins, was present 

 in certain of the whales with ventral white areas, although a more common co-existent marking (found 

 in 48% of the sample) was a combination of the half-white lower jaw with a white margin to the upper 

 jaw (Plate I, fig. 2), occasionally accentuated by some white around the gape. 



It is fairly clear from Table 4 that the sexes do not differ in their colour markings. Matthews, who 

 does not separate males from females when discussing the colour of southern sperm whales, has 

 employed similar categories and his results are included in Table 4. In general they are not unlike 

 the Azores proportions: category 7 is an exception, and none of the Azores whales bore light flecks 

 upon the flukes observed in 7% of the southern whales. But the present sample is a comparatively 

 meagre one, and these differences alone do not suggest that colour variation in Azores whales is 

 significantly different from that of southern stocks. Ohno & Fujino (1952, p. 133) have also reported 

 on the body colour of southern sperm whales from the Antarctic, and Omura (1950, p. 92) has reported 

 on those from the North Pacific. Comparing all four samples, it is not possible to distinguish any 

 clear-cut difference between these whales from different seas. 



Table 4. Colour variations of whales examined at Horta in 1949. Where possible 

 variations are compared zvith those recorded by Matthezvs (1938) 



Colour marking 



1 Uniformly pigmented except for slight streaking 



2 Ventral white splash 



3 Ventro-lateral white or light grey streaks 



4 Ventral white splash and ventro-lateral streaks both present 



5 Light flecking on dorsal fin or posterior dorsal humps 



6 Lower jaw half-white or more downwards from alveolar 



margins 



7 Lower jaw half-white and white margin to upper jaw 



Number of whales ivhose colour zvas recorded 



In his account of the progressive pigmentation of the foetus (1938, p. 119) Matthews implies that 

 the extension of dorsal coloration towards the ventral surface is not completed until the foetus has 

 achieved a length of approximately 3 m. However, the colours of the five small foetuses from Fayal 

 (Table 5) suggest that pigmentation can be completed at a much smaller size, when the foetus is no 

 more than 0-2 m. long. Moreover, Beddard (19 15) described the colour of a southern sperm whale 

 foetus 0-5 m. long as brownish black and mentioned no unpigmented areas. In Table 5 also, the notes 

 on areas of pale pigmentation do not seem to suggest that the spread of pigment is always from above 

 downwards. 



The head whorl is a characteristic marking in flecks and streaks on the lower part of the head in 

 some whales. A well-defined and extensive head whorl was regarded by old-time whalemen (Beale, 

 1839) as a sign of comparative age in the sperm whale. Matthews (1938, p. 1 19) doubts this assump- 

 tion but he figures in his Plate V a well-developed head whorl. At Horta in 1949 it was only possible to 

 record the degree of development of this character in a few individuals, because it was the custom to 

 strip ' blackskin ' from the whales as soon as they were hauled into the slipway (Clarke, 1954a, p. 343), 

 and this practice disfigures and obscures the whorl. A whale of 16-0 m. (Clarke, 1954a, Plate XVI, 

 fig. 5), where the whorl was so much developed as to make the animal ' grey-headed ', was found to 

 be physically mature. 



