1865.] OF PHYSALUS ANTIQUORUM. 207 
Heddle in his description of a female specimen of Physalus duguidii 
(P. Z.S. 1856, p. 188), which was of nearly equal size. 
From these parallel columns the correspondence between the rela- 
tive dimensions of the two species will readily be perceived. 
Physalus Physalus 
anti- duguidii. 
quorum 
ft. in ft. in 
Length from tip of beak to end of tail .........+.+00-. 60 0 | 50 0 
Head, from tip of beak to centre of orbit (along upper jaw)) 11 7 9 5 
Head, from tip of beak to centre of orbit (along lower Jaw) 13 0] 11 3 
Centre of orbit to anterior portion of pectoral fin ...... 8 2 5 3 
Between dorsal fin and root of tail ......-.eeeeeeeeee ets 10 0} 14 0 
Girth of body behind the pectoral fin.............2000- 38 0 | 23 0 
Girth of body at posterior termination of ridges ........ 1S "O" 19.3 
Girth of body at the penis (and close behind dorsal fin)..| 16 0 | 11 7 
Mr. Blaker estimated the weight of the animal at 45 tons, and 
was of opinion that about 4 tons of oil might be extracted from the 
carcase. Thus it would appear that the weight of the Physalus 
antiquorum is inconsiderable, when compared with that of a Balena 
mysticetus of equal length—the probable weight of the latter, ac- 
cording to Scoresby *, being 70 tons; and of this he allows 30 tons 
for the blubber alone. 
With regard to colour, the head and back were black ; the chest 
and throat of a brownish shade, and having the usual plaited cha- 
racter of the Balenopteride. Some of the crests of the ridges were 
deep brown, with the grooves or furrows of a lighter hue, even to 
yellowish white; other ridges had light-coloured crests, with their 
corresponding furrows greyish black. From the posterior termina- 
tion of these folds backwards the skin was yellowish white. The 
pectoral fins were dingy black above, whitish beneath, as also was 
the skin of the body beneath their bases; this was most marked 
behind, where the whitish colour was continuous with that posterior 
to the ridges. 
In the specimen of Physalus minutely described by Mr. Heddle 
(P. Z.S. 1856, p.193), after mentioning that the back is black, with 
some grey spots, and the belly white, he further says, ‘‘ When viewed 
obliquely, on the other hand, the whole dark portion of the animal 
seemed a dull leaden grey—a deception arising, no doubt, from the 
refraction of the light from the polished surface.” 
In the present specimen I observed something similar, which I 
am inclined to believe was caused by the fact that the epidermis 
consisted of several layers—the deeper and thicker intensely black, 
but the more delicate and superficial of a much lighter greyish brown 
hue, allowing, however, under certain circumstances, the deep black 
colour to show through, at other times reflecting its own paler tint. 
Of the parallel ridges with their corresponding furrows I counted 
on the one side as many as between forty-five and fifty, which would 
* « Arctic Regions,’ Edinb. 1820, vol. i. p. 462. 
