GREAT WEEVER. 
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from the north of the Sound off the fishing-village of Molle, which 
is clearly an intermediate form between the supposed species last 
mentioned. Its length is 237 mm. There are 6/28 rays in the 
2 
dorsal fin and — in the anal. The greatest depth of the body is 19 % 
30 
of the length — in the deepest typical specimen of Tr. draco that 
I have measured, it was 17.3 °/. The least depth is 6.3 % of the 
length and 13.3 % of the second dorsal fin; in typical specimens of 
Tr. draco it is at most 5.9 % and 11.9 % respectively. The length 
of the base of the second dorsal fin is only 47.7 % of the length of 
the body; in typical specimens of Tr. draco it is at least 49.2 f. 
The length of the lower jaw is 13 % of the length of the body. 
53.9 % of the length of the head, and 27.4 % of the length of the 
second dorsal fin ; the highest corresponding ratios I have found in 
typical specimens of Tr. draco are 12.4, 52.4 and 24 respectively. 
Above the anterior corner of each eye there are 3 spines; in per- 
fectly typical specimens of Tr. draco I have never found more than 
2. As far as I can judge from six measured, typical specimens of 
Tr. draco , 3 <y and 3 9? however, it is most correct to regard this 
intermediate form, though a specimen, as being, in most of these 
peculiarities, the result of an abnormal development of the external 
female characters. — Cf. with regard to the influence of the sexual 
characters on the development of form in the Salmonoid family, Smitt, 
Riksrnuseets Salmonider , Vet.-Akad. Ilandl., Vol. XXI, No. 8, pp. 
204, 289, and several other passages. 
The body of the great Weever is long, compressed, 
and thickest at the top of the head, but even there 
the greatest thickness is only 2 / 3 of the greatest depth 
of the body. The length of the head varies between 
21 and 24 % of the length of the body. The longi- 
tudinal diameter of the eyes in young specimens until 
about 250 mm. long, is between 21 and 20 % of the 
length of the head; in older specimens it is between 
18 and 17 %. The scales of the body are oblong and 
set in very distinct, parallel, transverse rows, which 
run obliquely downwards and backwards, and are about 
80 in number". The cheeks, temples and operculum 
are covered with very small scales. The nostrils are 
small and situated above the preorbital bone: the an- 
terior, which is the larger, has a grooved flap in the 
posterior margin; the posterior looks like a slit. The 
first three spinous rays in the first dorsal fin are fairly 
close together at the roots, the last three farther apart. 
The second or the third ray is the longest. We may 
sometimes find one or two of the rays longitudinally 
(sagittally) divided from in front. The fin may be 
hidden in its groove, but also admits of being sharply 
raised, so that the first ray points somewhat forward. 
The second dorsal fin, like the anal, which is still longer 
than it, is fairly uniform in height: the rays of the 
latter fin are thick and covered with a skin, which 
projects at the side almost like a flap. The caudal fin is 
a In the lateral line their number is from 77 to 85. 
truncate or only slightly concave. The pectoral tins 
are truncate, with 15 or 16 rays, the two uppermost 
being generally simple, the next 8, 9 or 10 quadrifid, 
or the last of them deeply bifid, and the last 5 or 6 
thicker and bifid at the tip, or the lowest ones simple. 
In the axil is a broad dermal flap, which is scaleless, 
but in other respects resembles the structure which 
exists at the same spot in Brama (see above). The 
ventral fins are set close together and small, measuring 
between 8 and 10 % of the length of the body. The 
lateral line is almost perfectly straight and runs nearer 
the back than the belly, but slopes somewhat down- 
wards at the base of the caudal fin. 
The Great Weever is adorned with fairly bright 
colours, which in a strange way shift into one another 
in the form of broken, oblique, narrow bands. The 
first dorsal fin is dark in front, with dense, large, black 
spots and reddish brown rays, and light behind. There 
is a dark spot on the anal fin too, near the ninth ray. 
Idle posterior dorsal, the colour of which, with the 
exception of the spot, is reproduced in the anal, is 
whitish at the base, with a yellow stripe along the 
middle, and edged with blue. For the other details of 
the coloration we may refer to the figure. 
As the abdominal cavity is fairly small, though it 
extends even behind the vent, the digestive canal lies 
in spiral coils. The stomach small, but fairly thick 
and firm. Six pyloric appendages. The liver consists 
of two lobes, the left considerably larger than the right, 
to which the gall-bladder is attached. No air-bladder. 
The urinary bladder long and fairly narrow. The 
generative organs are situated in the posterior part of 
the abdominal cavity. The dorsal column consists of 
40 — 42 (10 or 11+30 or 31) vertebra?. 
No external difference between the sexes in this 
species is yet known. Though Costa states that the 
male has only 5 spinous rays in the first dorsal fin, 
while the female has 6, this difference, in Sweden at 
least, does not hold good. In the females, however, 
as a rule, the head seems to be longer and the distance 
from the middle of the tip of the snout (which is some- 
what. concave, as the preorbital bones project forward) 
to the beginning of the dorsal fin so much greater than 
in the males, that in 3 females and 4 males we have 
found the length of the lower jaw, without exception, 
in the former less, in the latter more, than 63 % of 
Scandinavian Fishes. 
17 
