470 CALIFORNIA ACADEMY OF SCIENCES. 98 
long and spear-shaped, very much more slender in pro- 
portion to its length, not hollow and not receiving any of 
the air bladder. ‘This structure is seen in Gerres cinereus 
(Walbaum), in Gerres peruvianus Cuvier & Valenciennes, 
and in Gerres lineatus Humboldt, as also in several West 
Indian species. 
Fuctnostomus californiensis is generally common along 
the west coast of Mexico, from Guaymas to Panama. 
It is probably, however, not found in the West Indies, 
the closely related Aucznostomus harengulus being appar- 
ently a different species. The specimens called califor- 
niensis by Gill, having the premaxillary groove semi- oval 
or ()-shaped, seem to represent the adult of this species. 
Those called gvacz/7s, with the premaxillary groove linear, 
are the young or half-grown. Still others, especially 
adults, have the premaxillary groove round, forming a pit, 
and every intermediate character may be found. 
At first we thought it possible to separate calzforniensis 
and gracilis as distinct species. The careful re-examina- 
tion of some 200 specimens leaves us wholly unable to 
separate them, as all grades of variation occur. Appar- 
ently the premaxillary groove is linear in the young, grow- 
ing broader with age, but the changes very irregular. 
The name Hucrnostomus californiensis has priority over 
E. gracilis. 
Norre.—The genus Gerres was established by Cuvier 
in the second edition of the Regne Animal, the name 
being based on seven species as enumerated by him, 
rhombeus, oyena, aprion, poteti, lineatus, argyreus and 
filamentosus. One of these species must, therefore, be 
chosen as the type of Gerres. In 1842, Ranzani estab- 
lished the genus Deapterus on auratus, a species closely 
related to rhombeus, or rather to the allied o/7sthostoma. In 
1850, the name Catochenum was proposed by Cantor as 
