92 “TERRA NOVA” EXPEDITION. 
that these whales may possibly get whiter with age; but this idea was refuted by 
the fact that some of the whitest whales, seen at the Bay of Islands, were very 
small and showed signs of immaturity. Moreover, an unborn foetus (133 feet in 
length) was found to possess exactly the same coloration as the mother. They were 
both coloured as in text-fig. 2, No. 2. 
All the specimens examined were black on the dorsal surface, and most of them 
had some white on the ventral surface. Two were almost entirely black all over. 
The regular way in which the dorsal pigmented area encroached upon the white 
ventral region was very marked in the various individuals: the three points of black 
in the posterior half of the animal, which were barely indicated im No. 1 type 
(text-fig. 2) became more pronounced in No, 2, and in No. 3 formed bands round 
the abdomen ; in No. 4 they coalesced and spread out over the entire ventral surface, 
with the exception of two spots below the dorsal fin and a small area below the 
mandible. 
Fic. 3.—Ventral surface of a New Zealand Humpback whose pigmentation is between 
Nos. 3 and 4 in text-fig. 2. 
The mode of spreading of the pigment on the ventral surface is shown in 
text-fig. 3, which represents the type between Nos. 3 and 4 (text-fig. 2). 
Over the lighter areas the pigment occurred in oblique lines of flecking, which 
converged on either side towards the mid-ventral line. All the individuals, 
including the foetus 135 feet in length, were dappled like grey horses. The dapple- 
markings, which were particularly noticeable on the shoulders, pectoral fins, flanks 
and tail, consisted of white spots, rmgs and streaks on the black pigmented areas, 
and the same marks in black on the white areas. These markings are shown in 
text-fig. 4, A; they were quite distinct from the scars made by rocks and barnacles. 
In the whiter individuals there were often patches of grey on the white ventral 
surface, and especially at the junction of black and white areas in the neighbourhood 
of the dapple markings. The grey colour was due to a diminution in the amount 
of black pigment in the Malpighian layer of the epidermis. 
The interior of the mouth had a grey appearance, with the exception of the 
narrow strip of pink palate which made a keel-lke partmg between the greyish- 
white hairs of the ranges of baleen-plates. 
The tongue was of a darker grey colour than the hairs of the baleen-plates. 
