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 

 abdominal region, they are rounded off upon their posterior margin,, and truncated upon their 

 anterior margin. Kadiating 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 calif or- 

 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. 



