PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 29 
LABRIDZ. 
33. Pimelometopon pulcher (Ayres) Gill. 
Very abundant in the kelp outside the bay. 
SPHYRAINID AL. 
34. Sphyreena argentea Girard. 
Very abundant outside the bay in the fall. 
ATHERINID. 
35. Chirostoma californiense (Girard) Gill. 
Exceedingly abundant. 
36. Atherinops affinis (Ayres) Steindachner. 
Searcely less common. 
37. Leuresthes tenuis (Ayres) Jor. & Gilb. (gen. nov.) 
Leuresthes, gen. nov., allied to Atherinops Steindachner, but with the 
teeth wanting or reduced to slight or deciduous asperities. In the spe- 
cimens which we have obtained of this species no teeth whatever are . 
observable. 
The much greater width of the posterior portion of the premaxillary 
in Chirostoma, Atherinops, and Leuresthes serve to distinguish these 
genera from Atherina, in addition to the differences in the form of the 
mouth. Labidesthes Cope has, like Atherina, a slender premaxillary, 
but the mouth is curved and the jaws much produced forwards. The 
group called by Girard Heterognathus has likewise a broad premax- 
illary. It is probably not separable generically from Chirostoma, 
although the lower jaw is much stronger and some teeth are present on 
the vomer. © . 
Leuresthes tenuis is occasionally taken in San Diego Bay, but it is 
much less abundant than the others and attains a smaller size. 
MUGILID. 
38. Mugil mexicanus Steindachner. 
Very abundant in San Diego Bay. Our specimens have the anal IIT, 
8, instead of III, 7, as stated by Dr. Steindachner. 
SCOMBERESOCIDZ. 
39. Hemirhamphus sp. incert. 
The young of a species of Hemirhamphus is very abundant in San 
Diego Bay. We are at present unable to identify it with any of the 
known species, but having seen no specimens over four inches long, we 
