408 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 
(lark points. Scales small, smooth, ami firm, closely imbricated, their 
edges cremate. Maxillary not reaching to pupil, rremaxillary very pro- 
tractile, carved, its i)Osterioi' portion broad. Lower jaw shorter than 
upper. First dorsal fin over front of anal, much nearer base of caudal 
than snout. Eye equal to snout. Ilead ; depth 5. D. V-I, Oj A. 1, 
2L* ; Lat. 1. 75. L. 5 inches. Coast of California; abundant in San Diego 
Lay. 
(Athcrinoims tenuis Ayres, Proc. Cal. Acad. Nat. Sci. 13G0, 76.) 
19 §.— LAIIIDJKSTIIIES Cope. 
(Cope, Proc. Amer. Phil. Soc. Phila. 1370, 435: typo Chirostoma sicculum Cope.) 
This genus differs from 21enidia chiefiy in the prolongation of the jaws, 
both of which are produced into a short depressed beak. a pair 
of forceps ; i(T 0 iu}^ to eat.) 
039. !L. sicciiSuss Cope.— Rroofc Silverside; Slcqyjaclc. 
Pale olive- green, translucent; lateral silvery band very distinct, 
scarcely broader than pupil, bounded above by a dark line ; back dotted 
with black. Lody elongate, very slender, compressed. Head long, flat- 
tish above, narrow below. Snout slender, conic. Premaxillaries broad 
])osteriorly, very protractile, produced forwards, the snout longer than 
the large eye. Edge of upper jaw strongly concave. Teeth very slender, 
mostly in one series, forming a narrow band in front. Scales small, 
thin, with entire edges. Spinous dorsal very small ; soft dorsal short. 
Anal fin long ; caudal forked ; pectorals moderate. First dorsal inserted 
somewhat behind the vent. Head 4^; depth 0; eye 3^ in head. D. 
IV-I, 11 ; A. I, 23 ; Lat. 1. 75. L. 3^ inches. Ponds and sluggish 
streams; ]\[ichigan to Iowa and Tennessee; locally abundant; a very 
graceful little fish. 
{Chirostoma sicculum Cope, Proc. Ac.'td. Nat. Sci. Pliila. 1865, 31 : Lahidestlics sicculus 
Cope, Proc. Amer. Phil. Soc. Phila. 1870, 49.) 
199. — yiEIVIBilA* Bonaparte. 
Silversides. 
(Argyrea DcKay : BasiUchthys Grd. : Lahidestlies Cope.) 
(Bonaparte, Fauna Italica, about 1340: typo Aiherina menidia L.) 
Body elongate, more or less compressed. Head oblong, compressed. 
IMoutli small, the gape curved, very oblique, usually not reaching the eye; 
* Chirostoma Swainson, Classin. Fishes, etc. 1859, 24^ {= Athcrinoidcs Bleeker= Jt/icri- 
iiichthys Bleeker = //etow/nat/iws Grcl., all these nominal genera based on the same type, 
Athcrina humholdtiana Cuv. &. Val., from Mexico), is distinguished from il/cHidm by the 
very long and strong mandible which protrudes beyond the upper jaw. There are a 
few vomerine teeth, and the premaxillary is extremely i)rotractile. 
