34 ZOOLOGY. 
4°. Atherina macrophthalma Aaass.,* A. brasilensis, Cuv. and Vau.; from the bay of Rio 
de Janeiro. 
5°. Atherina bonariensis, Cuv. and Vau., from Buenos Ayres. 
6°. Atherina lichtensteinii, Cuv. and Vau., from Montevideo. 
And, in all probability: Atherina regia, Hume.,} from Peru, and Atherina lessonit, Cuv. 
and Vau., from Brazil. 
The genus Hrreroenatuus is based upon the elongation of the lower jaw, which projects 
considerably beyond the upper one. No teeth on the palate, or else in a rudimentary state only. 
Atherina humboldtiana and A. vomeriana, Cuv. and Vat., both from Mexico: whether from the 
fresh or salt waters, it is not stated. 
In all Atherinopsis, Basilichthys, and Heterognathus, the intermaxillaries constitute the upper 
arcade of the mouth at the exclusion of the maxillaries, which are situated behind the latter. 
This character will distinguish them at once from Atherina proper. 
Genus BASILICHTHYS, Girard. 
Gen. cHar. Intermaxillaries constituting the upper part of the mouth, the maxillaries 
being placed behind. Head and snout subconical; upper jaw protruding beyond the lower. 
Small teeth on both jaws; none on either the vomer or palatines. Upper surface of the head 
scaly. 
Syn. Basilichthys, Grp., Pro. Acad. Nat. Sc. Philad. VII, 1854, 198. 
Oxs. Like Atherinopsis, the present genus includes species of its family which are unprovided 
with teeth of any kind on the upper roof of the mouth. The mouth itself has the sanie general 
structure as regards the disposition of the intermaxillaries and maxillaries, but the conical 
shape of the head, and the protrusion of the upper jaw beyond the lower, will constitute the 
generic feature of Basilichthys. 
BASILICHTHYS MICROLEPIDOTUS, Girard. 
Pirate XXX, Figs. 6—9. 
Spec. car. Upper surface of head depressed and subeconvex. Cheeks and upper portion of 
opercle covered with conspicuous scales. Origin of anal considerably in advance of anterior 
margin of second dorsal. First dorsal opposite the middle of space between anals and ventrals. 
Caudal forked. Ground-color yellowish brown, dotted with blackish ; a silvery grey band along 
the middle of the flanks. 
Syn. Atherina microlepidota, Jen. Zool. of Beagle, IV, Fish. 1842, 78, Pl. xvi, fig. 1, la, 10. 
GurcH. in Gay, Hist. de Chile, Zool. II, 1848, 253. 
Basilichthys microlepidotus, Grp. Acad Nat. Sc, Philad. VII, 1854, 198. 
Peje rey, vernacular. 
Drscr. The general form is elongated, subfusiform, and slender; the back being rounded, 
whilst the flanks diminish considerably in thickness from the silvery band towards the medial 
line of the belly. The greatest depth of the body, measured above the insertion of the ventral 
* Pisce. Brazil, 1827, Pl. xlvii, Fig. 1. 
t Rec. d’Obs. de Zool. et d’Anat. Comp. I, 1833. 
