LOPHOBRANCHS. 
663 
excluded embryos on their ventral side. In the great 
majority of cases it is the males that have to perform 
this duty, just as the males of the Pycnogonoid fa- 
mily carry the lumps of eggs on their feet. But in 
Solenostomus the ventral fins of the female coalesce 
longitudinally with the ventral side so as to form a 
sac, in which the fertilized eggs are stored and deve- 
loped. 
Of the two families of this series there occurs in 
the Scandinavian fauna only the 
Fam. S YNGJN ATHIDfE. 
The greater part of the margin of the branchiostegal membrane united to the body , leaving only at the top , above 
and just behind the end of the operculum , a small , fissure-like gill-opening on each side. 
This family, as defined" by Kaup / j , includes the 
great majority of the Lophobranchs, with about 150 
species, distributed among 15 genera. All the Syn- 
gnathoids that occur in the Scandinavian Fauna, belong 
to Gunther’s 0 subfamily Syngnathince, which is dis- 
tinguished from the Sea-horses (Hippo campince) — with 
their descending (prone) head, elevated occiput, and 
more or less tumid body — by an evenly elongated 
form of body, with the head prolonged in the same 
direction as the trunk and with the latter only slightly 
thicker than the caudal part. In the Syngnathince , too, 
the tail is never so developed into a prehensile organ 
as in the Hippo campince. 
The above-mentioned rings formed by the plate- 
armour of the body are composed (fig. 169) on the 
Fig. 169. Schematic transverse section of a Syngnatlms. Magnified. 
After Moeeatj. A, transverse section of the trunk; 1 — 1 ', 2 — 2', 
and 3 — 3' the paired plates; 4, the ventral plate. B , transverse 
section of the tail. 
trunk (in front of the vent) of 7, 8, or 9, and on 
the tail (behind the vent) of 6 or 4 plates, so ar- 
ranged that the former make up 3 or, at the end of 
the trunk, 4 pairs and an unpaired ventral plate, which 
disappears behind the vent, while either the uppermost 
or the lowest pair disappears either behind the end of 
the dorsal fin or even behind the vent. As the paired 
plates are bent at greater or less angles, longitudinal 
carinae are formed on the sides of the body, three on 
each side of the trunk or even to the termination of 
the dorsal fin, and two on each side of the tail, where 
its section is quadrangular. But in many cases the said 
angularity is slight or absent, while the skin that covers 
the plates grows comparatively thick, rendering the 
body smoother, the plates and carinae more indistinct 
or even imperceptible. 
As in the rest of the Lophobranchs and a great 
proportion of the Hemibranchs, the snout is elongated 
and bears at the tip the gape, which is almost vertical 
when closed, with the ascending uncler-jaw forming the 
extreme margin of the head in front. In the Deep- 
nosed Pipefish (Syngnatlms typhle) the elongation of 
the snout is produced in the following manner. The 
ethmovomerine part is elongated like a staff, and coasted 
below by the long and narrow parasphenoid bone, while 
the frontal bones extend forward above in the form of 
long and narrow covering-bones over about half of the 
said elongation. The hyomandibular bone is an oblong, 
quadrangular but irregular, vertically set disk, which 
is united at a right angle below with the abnormally 
developed os symplecticum, which is directed forward, 
extends below the eyes, and sends out a branch obli- 
quely upward towards the lateral ethmoid (prefrontal) 
bone, while a second, still longer, horizontal branch 
meets a process in a backward direction from the 
quadrate bone. This horizontal branch of the symplec- 
ticum is partly naked (without covering bones) exter- 
nally, but is covered behind and below, throughout the 
greater portion of its extent, by the preoperculum. The 
vertical (posterior) branch of the preoperculum lies 
“ The family Syngnathidce as established by Bonaparte (Cat. Metod. Peso. Eur., 1846, p. 89) was differently defined, so as to 
exclude the Sea-horses. 
h Cat. Lophobr. Fish. Brit. Mus. (1856), p. 5. 
c Cat. Brit. Mus., Fish., vol. VIII, p. 153. 
Scandinavian Fishes. 
84 
