Jordan and Evermann. — Fishes of North America. 417 



67i>. UOBOSOMA PETENENSE (Giinther). 



Head 3i ; depth 24 ; eye 3i. D. 14 or 15 ; A. 20 to 23 ; lateral liue 40. 

 Maxillary exteuding to below frout of eye, which is longer than snout ; 

 jaws equal. Dorsal inserted slightly iu advance of ventrals and nearer 

 tip of snout than base of caudal, its filament reaching end of anal ; 12 

 scutes behind ventrals. Silvery, with a small, round black humeral 

 spot. Lake Peten, Yucatan. (Giinther.J 



Chalo'cssiis pelenensis, GOnthee, Cat., vii, 408, 1868, Lake Peten, Yucatan. (Coll. Salviii.) 



Family LXI. CLUPEID^. 



(The Herrings.) 



Body oblong or elongate, more or less compressed, covered with cycloid 

 or pectinated scales. Belly sometimes rounded, sometimes compressed, 

 iu which case it is often armed with bony serratures. Head naked, 

 usually compressed. Mouth rather large, terminal, the jaws about 

 equal; maxillaries forming the lateral margins of the upper jaw, each 

 composed of about three pieces. Premaxillaries not protractile ; teeth 

 mostly small, often feeble or wanting, variously arranged. Adipose eye- 

 lid present or absent. Gill rakers long and slender ; gill membranes not 

 connected, free from the isthmus. No gular plate. Gills 4, a slit behind 

 the fourth. Branchiostegals usually few (6 to 15). Posterior lower i^art 

 of opercular region often with an angular emargination, the tips of the 

 larger branchiostegals being abruptly truncate. Pseudobrauchite pres- 

 ent. No lateral line. Dorsal fin median or somewhat posterior, rarely 

 wanting. No adipose fin. Ventrals moderate or small (Avanting in Pris- 

 tigaster). Anal usually rather long; caudal fin forked. VertebrsB 40 to 

 56. Genera about 30 ; species 150 ; inhabiting all seas, and usually swim- 

 ming in immense schools ; many species ascend fresh wafers, and some 

 remain there permanently. The northern and fresh-water species, as in 

 many other families, difi'er from the tropical forms in having a larger 

 number of vertebral segments. {Chipeidcv, groups Clupeina and Dus- 

 sumieriina, Giinther, Cat., vii, 413-467, 1868.) 



Dussumieriin.tj: 

 a. Belly rounded, covered with ordinary scales; supplemental bones of nia.\illary very nar- 

 row; anal fin short. 



6. Ventral small; teeth small, persistent, on jawis, vomer, palatines, pterj'goids, and 

 tongue, 

 c. Scales of bieast not forming a corselet. 



(/. Species very small, with the teeth minute; a silvery lateral band; the dorsal 

 short, of 11 to 16 rays; ventrals inserted nearly under its front. 



,Tenkin8i.\, 203. 



dd. Species of moderate si/e, with moderate teeth; no silvery lateral band; the 



dorsal long, of 18 to 20 developed rays; the ventrals inserted much behind 



dorsal, much nearer base of caudal than tip of snout. Etrumecs, 204. 



cc. Scales of brea-st adherent, forming a ventral corselet, which covers the closed 



pectoral fins, except the upper edge and tip. Peukinsia, 205. 



aa. Belly compressed, armed with bony serra;; supplemental boues uf ma.\illary broad. 



F. N. A. 28 



