354 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



and opercles in about 8 rows. Color dark gray ; sides with round blackish 



spots on a ground color of grayish silvery 5 belly white ; fins spotted 



with black. Head 3| ; depth 6. B. 18 ; D. 17 ; A. 1 5 ; Lat. 1. 150. L. 4 



to 8 feet. A magaificent fish, by far the largest of its family, found in 



the Great Lake region and northward. 



(Esoxestor Dekay, N. Y. Fauna, Fislies,222, and of various authors, not of Le Sueur; 

 Thompson, Proc. Bost. Soc. Nat. Hist. 1850, iii, 163; Jordan, Bull. U. S.Nat.Mus.x, 54, 

 and of most late writers.) 



Order O.-APODES.* 



{The Eels.) 



Scapular arch free behind the cranium ; no praecoracoid arch. Air- 

 bladder, if present, with a pneumatic duct. Ventral fins wanting. 

 Maxillary and premaxillary more or less connate with other bones or 

 with each other, sometimes entirely wanting. Pharyngeal and oper- 

 cular apparatus often deficient. Vertebrae, in increased number. Ver- 

 tical fins without spines, usually -confluent around the tail. Gill-open- 

 ings usually narrow, separated by a broad isthmus, sometimes close to- 

 gether or confluent. No psendobranchia3. Body eel-shaped; naked, 

 or with rudimentary scales. 



As here understood, this order includes most of the old order of 

 Apodes, excluding as separate orders the Glanencheli (Gymnotldcc) and 

 the IcMliyocephaU {Monopteridcc). It thus includes the Holostomi, En- 

 chehjcepMli, and Colocephali of Cope, which may be united provision- 

 ally until the osteology of various aberrant forms is made known, (a, 

 privative; rou?, foot.) 



(Symbranchidce and Muranida; Giinther, viii, 12-145.) 



ANALYSIS OF FAMILIES OF APODES. 



* Vent much behind head; jaws not greatly produced; dorsal without spines, 

 t Muscular and osseous systems well developed. ^ 



a. Preoperclo wanting ; lower j)haryngeals wanting ; gill-openings very small. 



• MUK^NID^, 52. 

 aa. Preopercle present ; lower ijharyngeals present. 



6. Gill-openings well separated \ Anguillid.e, 53. 



hb. Gill-oi>euings contiguous; mouth very large, with small, sharp teeth. 



Synaphobranchid^, 54. 

 +t Muscular and osseous systems feebly developed ; gape very wide ; stomach ex- 

 tremely distensible SACCOPHARYNGiDiE, 55. 



**Vent under the pectorals; both jaws produced into a very slender beak; ))ody ex- 

 tremely slender; middle of dorsal with spines Nemichtiiyid^, 56. 



* Called Enchelycephali in the analytical table on page 81 



