SMELTS. 
863 
easier in the receptacles of a hatchery and in well- 
constructed ponds than in nature to protect the eggs 
and the defenceless fry from their numerous enemies. 
As soon as the voracity characteristic of the genus 
begins to awaken in the young brood, it is not diffi- 
cult to supply them with suitable food, either Ento- 
mostraca, where these can be procured in sufficient 
quantity — no doubt a rare occurrence — or lean beef 
or horseflesh, mixed with hard-boiled eggs and chopped 
fine. But important conditions of success are to have 
a constant supply of pure running water at a proper 
temperature, and to remove every diseased egg. The 
latter end is most conveniently attained by admitting 
the current of water at the bottom of the hatching- 
vessel and allowing it to run over at the top, the dis- 
eased eggs, which become white and rise to the sur- 
face, being thus carried away with the overflow. 
Here we have no space, however, for a full de- 
scription of Salmon culture in its details. The reader 
who desires more information on this head may con- 
sult either the Handbuch der Fischzucht und Fischerei 
by Max yon dem Borne, a work which we have often 
quoted, or Sir James Maitland’s History of Ilowie- 
town. In Swedish these questions are handled with 
ability by 0. G. Norback in his Handledning i FisJce- 
vdrd och Fiskafvel. 
Genus OSMERUS". 
Canine teeth on the vomer and tongue; two rows of small teeth in the anterior part of the lower jaw, one row 
of larger teeth in its posterior part, and, on the palatine hones; small teeth of uniform size, set in one row, on 
the inter maxillaries, the maxillaries, and the mesopterygoid hones. Length of the maxillaries as a rule 60 — 66 
% b , of the lower jaw as a rule 85 — 100 % c , of that of the head reduced. Number of rays in the anal fin greater 
than in the dorsal, hut at most 17, 12 — 14 of which are 
of the dorsal. Pyloric appendages few (at most about 
row along the sides of the body, only the anter 
According to the above limitation of the genus, 
based on the most generally adopted opinions, it con- 
tains only three species, very nearly related to each 
other, one from the basin of the Atlantic, the second 
from the Arctic Ocean, and the third from the basin 
of the Pacific. Its most prominent character consists 
in the dentition of the mouth and palate. The vomer 
is especially remarkable, its development having been 
arrested so that it is made up of the anterior part 
(the head) alone, and officiates merely as a point of 
attachment for two d large and widely separated, canine 
teeth. Another dental character, shared, however, by 
the following genus, is the presence of inner palatine 
teeth. On opening the mouth of a Smelt, we see a 
deep and narrow, longitudinal groove at the middle 
of the palate, furnished at the sharp edges with a row 
branched; and the base of the anal fin longer than that 
7) and short. Scales middle-sized, about 60 — 70 in a 
ior (10 — 22) being pierced by the lateral line. 
of small but keen teeth, which are set on the inner 
margin of the broad mesopterygoid bone, the largest 
bone on each side of the palatine arch. The pterygoid 
bone proper is toothless, consisting simply of a narrow 
osseous disk, which lies close to the outer margin of 
the mesopterygoid bone and unites the palatine and 
quadrate bones. All the palatine teeth are canines, 
but their development as such differs considerably, 
bein'? most advanced in the foremost and hindmost 
teeth. The largest teeth in the whole mouth, however, 
are as a rule the outermost in the transverse row 
belonging to the head of the vomer. The teeth in the 
lower jaw are also canines, the posterior larger and 
set in one row, the anterior set in two rows, with the 
smallest teeth in the outer row. The intermaxillary 
teeth are about equal in size to the last, and show at 
a From the Greek oo/.n]Qrig or ooyriQog, odorous. 
6 ’59'4 — G6'7 %, according to onr measurements of specimens in the possession of the Royal Museum. 
85:— 102-4 %. 
Orlrhree, or two pairs — one in front of and within the other — or five, in which case the inner teeth are smaller than the outer. 
Scandinavian Fishes. 
109 
