Jordan and Evermann. Fishes of North America. 417 



679. DOROSOMA PETENENSE (Giinther). 



Head 3| ; depth 2f ; eye 3*. D. 14 or 15 j A. 20 to 23 ; lateral line 40. 

 Maxillary extending to below front of eye, which is longer than snout ; 

 jaws equal. Dorsal inserted slightly in 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. (GiintherJ 



Chatotsstupetenensis, GONTHEB, Cat., vn, 408, 1868, Lake Peten, Yucatan. (Coll. Salvin.) 



Family LXI. CLUPEID^. 

 (THE HERRINGS.) 



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

 or pectinated scales. Belly sometimes rounded, sometimes compressed, 

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

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

 equal; ma'xillaries 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 part 

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

 larger branchiostegals being abruptly truncate. PseudobranchiaB pres- 

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

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

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

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

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

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

 many other families, differ from the tropical forms in having a" larger 

 number of vertebral segments. (Clupeidce, groups Clupeina and Dus- 

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



DUSSUMIERIIN.S:: 



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

 row; anal fin short. 



b. Ventral small; teeth small, persistent, on jaws, vomer, palatines, pterygoids, and 

 tongue. 

 c. Scales of breast not forming a corselet. 



d. 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. 



JENKINSIA, 203. 



dd. Species of moderate size, 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. ETRUMEUS, 204. 



cc. Scales of breast adherent, forming a ventral corselet, which covers the closed 

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



CM. Belly compressed, armed with bony seme; supplemental bones of maxillary broad. 

 F . N . A. 28 



