68 PROCEEDINGS OF UNITED STATES NATIONAL MUSEOM. | 
The whole fish is highly transparent when fresh, the outline of thé 
brain being clearly visible through the occiput. 
From Osmerus thaleichthys, which at first sight nearly resembles it, 
this species may be distinguished by the following characters: The 
slightly greater length and more tapering form of the snout, when 
viewed from above; the straight lower jaw, which in O. thaleichthys is 
considerably curved upwards toward the tip; the gradual declivity of 
the upper outline of the head, which in the latter species is straight 
with the line of the back; the larger eyes; the different arrangement of 
the teeth; the more elong hen body, much less curvate along the abdom- 
inal pacinee and the much greater distance between the tips of the 
pectorals and the base of the ventrals. 
Dimensions. 
No. 1. | No. 2. | No. 3. | No. 4. | No. 5. | No. 6 
a = = = —_—_—— —_ | 
Inches. Inches. | Lehane Inches. , Inches. | Inches. 
AUG TAINO AQUIN Se ce cnocele oticudnanodesss seponcosbesses 4:42) || © 24, 50)'|) 1 5257/0572 5.06 | 6.00 
Greatest depiiiotbodiyguse. a: - soos ces satenis\ seco as | 5d, . 58 | - 60 | 72 . 62 oD 
Length of head, to tip of lower jaw .-------.---. «-. | - 96 1°00) 21.13 125: T1252 
oneitudinallidiameter ofeye'.-.2-5..2-.--.ss0<0--6- 2h || . 23 . 30 | 29 Pay | 20 
UmterorDitalewaduh sa = et cejijcc se ceeajresee scence ane -19 . 20 -23 | -3l - 26 | 245 
Length of snout, to tip of upper jaw ..---..-----.--. | 23 oe) 28 | 30 | 28 | ool 
en suhy without Camda so 22 a\- am -eniniee a lek ismi=iale 3. 47 3. 84 4.42 4.87 4. 30 5. U9 
Tip of lower jaw, to adipose fin’ —-...----..:.---+-.-- 2. 97, 3. 00 3. 62 4.14 3. 60 4.31 
MM PLOTLOONs awe LOnVeN tals! 22 6 = = tence ete'= =1oel=1 Tay) | RaIt)) | 2.06 | 2.68), 2030 ent 
Men Suh Ol peChoraly es a2 wes = Se eee chew dao eece . 50 HOS 3 GE 72 | . 65 81 
SETG TO GOT CLONS Alle ersere c= see ctoe See tecsecionicleias dana seer . 56 . 64 SE . 62 . 69 
Gengtbrot ventrally. - 22-2 ea. 2 = an wlan nin 45 45 206 . 64 158 . 69 
Tip of lower jaw to-origin of dorsal. ..----.--.------| 2.00.) 2.15 2. 56 2.19 2. 40 2. 94 
eS HhrOMlOWeC AW sche ce ee Bae sos. seee ln sees as - 56 . 60 | . 68 . 70 | (608 24ieaeeeee 
Width of caudal peduncle SEAS e Roce dBA eR pOnEtesaaae | - 20 | 520) 24 | . 30 26 -ol 
1 | { 
Nos. 1, 2, and 3 are alcoholic specimens; the others were measured while fresh. 
The comparatively elongate form of this fish induced me to believe 
that-this species must be Q. elongatus Ayres (Proe. Cal. Acad. Sci., I, 
17, 1854), but as the latter ichthyologist transmitted examples of his 
species to Washington, and these examples were examined by Girard, 
and found by him to be identical with his Osmerus pretiosus (= Argen- 
tina pretiosa Grd. = Hypomesus olidtus (Pallas) Gill), there is no doubt 
that the foregoing is an undescribed species. 
There are thus four species of Microstomatide on the Pacific coast, 
United States, viz, Thaleichthys pacificus, Hypomesus olictus, Osmerus 
thaleichthys, and O. atienuatus. The first of these does not occur in the 
markets of San Francisco, but is sent down packed in salt from the 
Columbia River, also to some extent in oil, under the name of “ Colum- 
bia River sardines.” The other three are brought into the markets in 
a fresh state. Hypomesus olictus grows to the largest size, and is most 
highly esteemed of the three. Osmerus attenuatus is tolerably abundant 
in the markets during the spring and summer months. 
