676 
SCANDINAVIAN FISHES. 
Its least- depth, just behind the upward curve of the 
tip, is as a rule about 1 / 5 , but sometimes no more 
than 15 % of its length. The length of the lower jaw, 
which is as a rule about 1 / i (varying, however, in dif- 
ferent individuals between 30 and 21 %) of that of the 
snout, measures in adult specimens, at least after they 
have attained a size of 12 cm., distinctly more (gene- 
rally V 3 more) than the diameter of the eyes", but in 
young specimens (6 or 7 cm. long) is about equal to 
this diameter*. The eyes are also comparatively smaller 
than in the Great Pipefish. In young specimens (6 or 
7 cm. long) their diameter is about 74 or even 28 % 
of the length of the snout, but with increasing age this 
percentage sinks to about 15 or even 14. In the said 
young specimens the postorbital length of the head 
measures about 38 — 36 % of its entire length, or about 
2 / 3 (at least 64 %) of the length of the snout; but in 
older specimens this proportion sinks to about 30 or 
29 % of the length of the head, or 50 — 46 % of that 
of the snout. 
The gill-openings are comparatively somewhat 
larger than in the Great Pipefish, their length being 
about 2 / 3 of the diameter of the eyes; but they are 
otherwise of the same form and position. 
The pectoral fins are of the same obtuse shape as 
in the Great Pipefish, or even broader, and generally 
contain a greater number of rays. 
The dorsal fin is longer and lower than in the 
Great Pipefish, in the former respect coming nearer the 
Lesser Pipefish. It is also set comparatively further 
back, this being due to the shortness of the tail. Here, 
however, we find a distinct sexual difference in the 
Deep-nosed Pipefish: in the females the trunk is com- 
paratively longer than in the males, and the dorsal and 
anal fins are consequently situated further back. The 
two preceding species represent in this respect that- di- 
rection of development which has been fixed by the 
preponderant influence of the male characters. In the 
Deep-nosed Pipefish the distance between the dorsal 
fin and the tip of the snout, to the best of our know- 
ledge, is never less than 397 2 % of the length of the body, 
in the males hardly more than 42 %, in the females 
about 44 %, and in young specimens sometimes 47 %. 
It generally begins on the last ring of the trunk (the 
anal ring), sometimes on the penultimate one. The 
base of the fin (12 — 137 3 % of the length of the body) 
occupies in most- adult specimens 10 rings, in some 9 
or partially 11, and in young specimens 8. Its height, 
which is only slightly greater at the middle than at 
either end, is generally equal to the length of the 
lower jaw. 
In the Deep-nosed Pipefish as in the Great Pipe- 
fish, we have not been able to find more than 3 rays 
in the anal fin. According to Krdyer and Day, how- 
ever, it may contain 4 rays. It is set- at a distance 
from the tip of the snout that measures in the males 
about 40V 2 — 42Va in the females about 44 7 2 — 45 7a 
% , and in young specimens as much as 487 2 % of the 
length of the body. 
The caudal fin, which is distinguished by the 
bluntly pointed form of the hind margin, measures as 
a rule about 37 2 01> 4 % of the length of the body, 
and thus corresponds most nearly in this respect to 
the caudal fin of the Lesser Pipefish. But in con- 
sequence of the greater length of the head in the 
Deep-nosed Pipefish, the length of the caudal fin is 
only about x / 5 of that of the head, though it- varies 
between 18 and 25 % thereof. In most cases it con- 
sists of 10 rays; in one single instance we found 8. 
All the fin-rays are of the same type as in the 
two preceding species; but in the caudal fin they are 
sometimes articulated. 
Of the coloration of the Deep-nosed Pipefish Fries 
remarks: “In both localities, both in the Baltic and 
the Cat-tegat, two colour-varieties occur, the first green 
with yellow spots and with the belly shading decidedly 
into brassy yellow, the second olive-brown strewn with 
numerous whitish dots and spots and with whitish belly. 
These two varieties are not constant, however; we find 
a series of intermediate forms between them. They 
do not stand in any fixed relation either to age or 
sex.” The relation of these two colour-varieties to 
each other has been explained in recent times by 
Heincke 0 as follows: 
“The power Avhich the Syngnatlii possess of ad- 
apting their colour to their environments, is the most 
perfect instance of the kind that we know among 
fishes. If we place some Deep-nosed Pipefishes in a 
large aquarium, together with a quantity of seaweed 
( Zostera marina) such as that, which grows in the 
“ In a female 255 mm. long, from Bohuslan, the longitudinal diameter of the eyes is only 55 % of the length of the lower jaw. 
b In the fry the lower jaw is, of course, considerably shorter — cf. A. H. Malm’s figures (1. c.). 
c Schriften des Naturwissenschaftlichen Vereins fur Schleswig-Holstein, Band I, p. 257. 
