104 
U. S. P. R. R. EXP. AND SURVEYS-ZOOLOGY-GENERAL REPORT. 
and dichotomised rays, and a rudimentary, undivided one upon their external edge. The pec¬ 
torals are well developed, posteriorly falciform, and terminating into a point. 
Br. VI: VI; D VII, 13 ; A I, 27 ; C 5, 1, 8, 7, 1, 7 ; V I, 5 ; P 15. 
The scales are large, constituting but thirteen longitudinal series upon the line of greatest 
depth of the body. Longer than deep on the dorsal region, and deeper than long on the 
abdominaFregion, they are rounded off upon their posterior margin, and truncated upon their 
anterior margin. Radiating grooves may be seen upon the posterior section of the scale only. 
The cheeks, operculatur apparatus, and the upper surface of the head, are covered with large 
and imbricated scales, similar to the scales of the body, except that their outline is subjected to 
infinite variations. 
The dorsal region above the silver band is greyish brown, as also the upper surface of the 
head ; the silver band is margined with bluish black. The flanks, sides o head, and belly are 
light brown in the young and silvery in the adult. The fins are olivaceous and unicolor. 
References to the figures .—Plate XXII c, fig. 1, represents, size of life, Atherinopsis califor- 
niensis, from San Francisco. Fig. 2, an outline of the fish seen from above. Fig. 3, an outline 
of the head from beneath. Fig. 4, a section of the body taken across its middle. Fig. 5 is a 
scale from the dorsal region. Fig. 6, a scale from the abdominal region. 
List of specimens. 
Catalogue number. 
No. of specimens. 
Sex and age. 
Locality. 
When collected. 
Whence obtained. 
Nature of specimens. 
Collected by— 
351 
5 
Adult_ 
San Francisco, California — 
1853 
Lieut. R. S. Williamson. 
Alcoholic_ 
Dr. Heermann ._ 
352 
2 
. .do_ 
...........-do.___ 
1853 
_do_ 
_do.__ 
Dr. Newberry_ 
L b 
353 
1 
_do___ 
1853 
Lieut. A. W. Whipple_ 
Dr. Kennedy ... 
354 
6 
Presidio, California_ 
1853 
Lieut. W. P. Trowbridge_ 
_do_ 
Lieut. Trowbridge 
355 
1 
San Die^rOj California.__ 
1854 
Major W. Emory_... 
_do_ 
A. Schott_ 
356 
2 
1853 
Lieut. W. P. Trowbridge_ 
_do.. 
A. Cassidy_ 
357 
5 
do _ 
1853 
353 
2 
1856 
_do_... 
E. Samuels_ 
359 
6 
_do___ 
1856 
..do. 
