BASKING SHARK. 
1145 
the diameter of the orbits, between those of the second 
pair three times the same diameter, of the third pair 
live times, of the fourth pair seven times, and of the 
fifth pair nine times, in each case according to Storer’s 
measurements. The gill-rakers (fig. 332) have claimed 
a special chapter in literature. They are long and line, 
apparently corneous, transversal setae, uniserial on the 
first and last branchial arches, biserial on the others. 
Even Gunnerus described them" as forming a kind of 
strainer; and a very characteristic indication of their 
structure is his opinion that, it was by clinging to 
them that the prophet Jonah escaped being engulfed in 
the maw of his captor — a Basking Shark, not a whale, 
being the monster that swallowed this remarkable man. 
In 1867 6 , without knowing what the objects were 
or whence they had come, but guided by their micro- 
scopical texture, Hannover determined some dry frag- 
ments of these gill-rakers, preserved in the Museums of 
Copenhagen, Kiel, and Christiania, as a kind of squa- 
mous or spinous growth belonging to some Ray. The 
same texture, answering to that of dentine, tvas detected 
by v. Beneden in 1871° in similar substances from the 
Antwerp Crag, and he assigned them to a Ray otherwise 
unknown, which he called Hannover a aurata. Steen- 
strup (1. c.) and, after him, Gervais (P. and H., 1 . c.) 
have since maintained both that these gill-rakers afford 
one of the most important characters of the genus Ce- 
torhinus, and that v. Beneden ’s find carries the existence 
of the genus back at least to the Tertiary epoch. 
The fins are very like those of the Porbeagle; but 
their outer (posterior) margin is less incurved. The first 
dorsal begins at a distance from the tip of the snout 
measuring about 40 — 36 %, and its base occupies about 
10—9 * i / 2 of the length of the body. Its height some- 
times measures, according to Storer, 14V 2 % of the 
length of the body. The distance between the two 
dorsal fins is about 1 8 1 / 2 — 1 9 % of the said length. 
The second dorsal and the anal fins are about 1 / s as 
large as the first dorsal. The superior caudal lobe 
measures about 19 — 21 % of the length of the body, 
and the inferior lobe is about 2 / 3 as long. The median 
breadth of the caudal fin, from the upper transverse 
groove, is about equal to the length of the base of the 
first dorsal. A little within the tip the under margin 
of the superior lobe has the same notch as in the Por- 
beagle. The pectoral fins are rather more than twice 
as long as broad. Their length is about 18 % of that 
of the body. The ventral fins, according to Pavesi’s 
figures, are obliquely quadrangular. Their length is 
about the same as the breadth of the pectorals. The 
preabdominal length is about equal to the distance be- 
tween the beginnings of the two dorsal fins. 
The thick skin is armed with sharp and strong 
spines — small in comparison to the size of the body, 
Fig. 332. Gill-rakers of the Basking Shark. A, an excised branchial 
arch, on a reduced scale, after E. Perceval Wright ( Nature , vol. XIV 
(1876), p. 313); B, part of a row of gill-rakers, nat. size, after 
Hannover and Steenstrup. 
“ . . . “fine, stiff, lustrous black strings, resembling bristles or horse-hair, all with one end attached to and hanging over cme side of 
a round, cartilaginous arch, of a thumb’s thickness”. 
1 D. Vid. Sels. Math. Natur. Skr., 5:te Rseklce, Bd VII, p. 489. 
c Bull. Acad. Roy. Belg., ser. 2, tom. XXXI, p. 504, pi. II, fig. 16. 
