SEA LAMPREY. 
1187 
and 3rd third of the length of the body. Mouth quad- 
rilateral. Opening to the throat very large, but accu- 
rately closed by six irregular and ragged subcartilagi- 
nous processes, which meet in the centre. Anterior lip 
transverse, convex on its outline, and emarginate at each 
end, where it unites with the lateral lips; these latter 
are wide and convex on their slender margins, uniting 
posteriorly below the edge of the lower lip, leaving them 
free above. Length of the snout to the eyes 5 %, and 
the diameter of the eyes lV 4 %, of the length of the body. 
Eyes distinct, lateral, covered with the common tegu- 
ments, and placed in a depression over the margin of 
the lower lip. Nasal orifice large, and surrounded by a 
raised margin; contracted, linear in front, circular be- 
hind; its distance from the tip of the snout 3 3 / 4 % of 
the length of the body. The branchial furrow occupies 
7 8 of the length of the body, is directed obliquely down- 
wards, and extends to a point above the lower angle of 
the lateral lips; the apertures are exceedingly small, and 
appear to be capable of being closed by their mem- 
branous edges. Such was Dekay’s description of this 
larva. It is said to be common in the muddy bottom 
of most streams in the north and west of New York 
State. Jordan and Gilbert explained it as a larva of 
Dekay’s Petromyzon appendix; and when Jordan and 
Fordice combined this nominal species with Petromyzon 
marinus, the larva, of course, had to be referred to the 
latter species. If the explanation is correct, the Sea 
Lamprey thus undergoes a metamorphosis similar to 
that of the following species, though not- in every de- 
tail. The mouth apparatus and the snout are entirely 
re-formed (see above). The eyes advance further for- 
ward from the gill-openings. The nostril loses its an- 
terior narrow part. The anal aperture is removed fur- 
ther back. The dorsal fin-growth is divided, and its 
beginning moved more to the front. A special caudal 
fin is developed; but the rudimentary anal fin disappears. 
Ammoccetes bicolor, which has also been referred to the 
present species, was said to resemble the developed Sea 
Lamprey more nearly in the dorsal fins and the position 
of the anus, though the eyes were still indistinct. 
The Sea Lamprey, as we have seen, has an exten- 
sive geographical range, embracing all the seas of Europe. 
According to Pallas the same species inhabits the Cas- 
pian Sea and ascends the Volga; but Kessler ranged 
this form as a new species, Petromyzon Wagneri. It 
would also appear uncertain whether we can still rely 
on Pallas’s statement that our Sea Lamprey also occurs 
in the Sea of Okhotsk. From “West Africa”, however, 
according to Gunther, the British Museum has received 
the true Petromyzon marinas; and this Lamprey has 
perhaps a more congenial habitat in the west of the 
Atlantic and the east of North America than in Europe. 
There it has even been landlocked in several lakes, and 
lives in these without ever finding its way to the sea. 
In this species we accordingly find the same state of 
things as among the Salmons, and the form landlocked 
in Cayuga Lake (Ithaca, N. Y.) was regarded by Wil- 
der as a distinct species, Petromyzon dorsatus, its dor- 
sal carina being particularly well developed. 
In Scandinavia the Sea Lamprey is found every- 
where from the extreme north, though of unfrequent 
occurrence. From the Vestmannaeyiar, on the south 
coast of Iceland, it was remarked by Krdyer, from the 
Faroe Islands by the elder Reinhardt. In Greenland it 
is unknown. In Norway, as well as in Bohusl&n and 
on the other coasts of Sweden, probably too in Denmark, 
many years may elapse without the catch of a single 
specimen being notified to the museums, and as a rule 
only solitary individuals are taken. In the Baltic, where 
it is so well knotvn on the coast of Blekinge, according 
to Nilsson, that it has a special name ( Sillapipare ) 
among the fishermen, the species penetrates so far that, 
according to Malmgren, “a fairly large and handsome 
specimen has been taken in the seine in Gammelstads- 
vik” (Southern Finland). 
All that is known of the life led by the Sea Lam- 
prey in salt water is that it swims like the Eel, bending 
the whole body in serpentine movements. Frequently 
it is taken from shore in the Herring-seine; and this 
would in all probability not happen so often, unless the 
Lamprey were moving about among the Herrings. Most 
of its time, however, it no doubt passes attached to 
stones or floating objects, such as driftwood, or boats, 
and to the fishes which it selects as its victims. Gun- 
nerus (1. c.) states that Sea Lampreys fix themselves in 
great numbers to the body of the Basking Shark and 
do not leave it until it is dead". The Sea Lamprey also 
attacks finer fish, such as Mackerel, Codfish, etc. Gesner 
relates 6 , on the authority of a Strasburg fisherman, that 
the Sea Lamprey attaches itself to Salmon ascending 
from salt water, and is thus conveyed far up the rivers. 
“ The same statement, given on the authority of Governor Christie of Bergen, appears in Kroyer, 1. e., p. 1038. 
b De Aquatilibus, p. 596. 
