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U. S. P. E. E. EXP. AND SUEVEYS—ZOOLOGY—GENEEAL EEPOET. 
6. FARIO STELLATUS, Grd. 
Plate LXIX, Figs. 5 — 8. 
Spec. Char. —Body elongated and fusiform; head well developed, contained four times and three-quarters in the total 
length; jaws equal; maxillary gently curved, reaching a vertical line, drawn posteriorly to the orbit, Anterior margin of 
dorsal fin a little nearer to the extremity of the mouth than the insertion of caudal fin. Back light olive ; belly light yellowish 
white. Bead, body, and fins profusely spotted with black. 
Syn.— Fario stellatus, Gud. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 219. 
Salmo stellatus, Grd.— Opkalloo, Wasco Indians.— Common trout, Vernacular. 
This is one of the most characteristic species of the genns inhabiting the northwestern waters, 
by the numerous spots which extend all over its head, body, and fins. The body is elongated, 
rather slender, compressed, fusiform in its outline ; the greatest depth, taken in advance of the 
dorsal, enters about six times in the total length, whilst the least depth, on the peduncle of the 
tail, is a little less than the half of the greatest. The back is rounded. 
The head is proportionally well developed, constituting the fifth of the total length. It is 
sub-conical in shape, the snout being rounded, and the jaws equal in length. The maxillary 
is rather slender ; its posterior half lanceolated, and slightly bent downwards ; its extremity 
extends to a vertical line draw at a little distance behind the orbit. The teeth are small; those 
on the shaft of the vomer are the most robust of all, and constitute quite an irregular series. 
Tbe eye is moderate in size, sub-circular in shape ; its horizontal diameter entering about six 
times in the length of the side of the head, once and a half in advance of the anterior rim of 
the orbit. The pre-opercle is much deeper than wide, narrower above than below, and slightly 
concave upon its external margin. The branchiostegal rays are eleven on either side, a3 
usual very flat and short. 
The fins are well developed ; the caudal constitutes a little more than the seventh of the 
total length ; it is emarginated upon its posterior margin. The dorsal is anteriorly higher 
than the whole fin is long ; its posterior margin is equal to about the.half of the height of the 
anterior margin, which is a little nearer the extremity of the snout than the insertion of the 
caudal. Its upper margin is nearly straight. A vertical line drawn through the middle of the 
base of the adipose would intersect the middle of the anal ; its posterior extremity, therefore, 
does not extend as far as that of the latter fin. The anal itself is deeper than long also, but 
its posterior margin is only the third of the depth of the anterior ; externally the fin is either 
straight or very slightly concave. The origin of the ventrals is situated opposite the fourth 
developed ray of the dorsal, the sixth in the series ; these fins are quite broad, and their tips 
are nearly even with the extremity of the posterior rays of the dorsal when bent backwards. As 
to the pectorals they are lanceolated, and broad upon their middle. 
Br. 11 : 11; D 11 ; 0; A 11 ; C 5, 1, 9, 8, 1, 4; V 9 ; P 13. 
The scales are of moderate development, sub-elliptical or sub-ovoid, narrowest anteriorly ; 
largest in the lateral line, and smallest on the dorsal region, where they are likewise deeper, 
compared to their length, than in the lateral line and on the abdominal region. The concentric 
stria are obliterated upon the centre of the scale and upon the posterior margin of those of the 
lateral line and abdominal region. As to the lateral line itself, it starts from the posterior 
upper part of the opercular apparatus, and by a downward curve reaches the middle of the 
thoracic region ; hence straightway and median to the base of the caudal fin.' 
Specimens of this species were collected on the first of January, 1855, Fort Steilacoom, 
