458 



CONTRIBUTION TO THE 



Pedio0I;ATi. Basal radii of pectoral fin elongate, reduced in number ; no interclavicles. Epiotios united with 

 each other above behind supraoccipital, and the first vertebra with the cranium by suture ; posttemporal broad, flat, 

 simple. Superior pharyngeals two, similar, spatulato with anterior stem and transverse blade. Basis cranii simple. 



Two families, the Antennariidm, with three, and the LophiidcB (LopJiius, Ealieutma, Malilie), with two, basal pec- 

 toral radii. They connect with the I'ercomorpjd by the Blenniidm and "BatracMdw. 



Hbtekosomata. Cranium posteriorly normal ; anteriorly with twisted vertex, to allow of two orbits on one side, 

 or one vertical and ono lateral ; basis not quite simple ; dorsal fin with jointed rays. Superior pharyngeals four, 

 the third longest, much extended forward ; inferiors separate. 



Embraces the family of Pleuronectidm. 



Plbctognathi ; cranium posteriorly normal ; the posttemporal coi'issilied with the epiotic, and undivided. The 

 elements of the mandible and usually the premaxillaiy and maxillary coossifled. Iuteroperculum a slender rod. 

 Superior pharyngeals laminar usually vertical and transverse. 



1 Maxillary distinct, a suboperoulum ; sup. pharyngeals vertical, transverse, fourth present, minute; ; 



TriacAinihidm. 



2 Maxillary coossifled, a suboporeulum ; basis cranii double, with tube. Pharyngeals vertical transverse, fourth 

 wanting; Ilalistidm. 



3 Maxillary coossifled, a suboperoulum and symplectio ; basis cranii simple. 



Pharyngeals transverse vertical, fourth present ; Tetrodontidce. 



Bo. more longitudinal, Diodonlidtr. 



4 Maxillary ooossiliod ; no suboperoulum ; symplectic not ossified ; intcrelavicles present. Fourth sup. pharyn- 

 geal wanting, 2d and 3d forming a vortical subconie mass ; Ostracioniidai. 



Tho contents of this order are heterogeneous, and it is questionable whether section fourth really belongs to it. 

 The Plectognaths are associated with the true peroiform fishes by Triaeanthus on their part, and the Acronurida 

 and (Jhaetodontidi/i on the other. Their affinities have never been, in my estimation, heretofore properly expressed in 

 the systems, whero they have always been arranged at a, distance from the higher PhytOOlysti. Yet the structure of 

 the swim-bladder, skull, scapular arch, caudal vertebral, pectoral fin, in fact, everything, combine to indicate their 

 position to be here. The shortened jaws, especially the maxillary of Acanthurux, remind one of Triacanlhus, and its 

 closely united slender femora, approach thoso of Baliltes. The coossilioation of the simplo posttemporal with tho 

 cranium confirms the affinity. 



Percomobphi. Bones of the mandible distinct, maxillary distinct. Cranium symmetrical, epiotios normal ; no 

 interclavicles ; posttemporal not coossifled with cranium. Basal pectoral radii not enlarged; humeri . suspended 

 (generally) from the scapular arch. Basal branohihyals three, inferior pharyngeals distinct ; superior pharyngeals 

 with tho third most generally largest. Sub and iuteroperculum present, plate-like. 



This extensive order embraces a great variety of forms, some of which may yet be regarded as forming distinct 

 orders. At present, I am not sufficiently sure of their exact definition to admit them as such. 



I. AiiacantMni. Basis eranii simple, no tube; posttemporal bifurcate, scapular foramen between scapula and 

 coracoid. Superior pharyngeals three, horizontal, third little larger. Borsal fin, rays flexible, jointed. Includes 

 the families Oadidce and Macruridtn, both with Isocercal caudal vertebra;. 



II. Haplodoci. Basis cranii simple flat, posttemporal simple undivided. Scapular foramen in centre of scapula. 

 Basal segments of pectoral fin live, elongate. Superior pharyngeals contracted, first and fourth wanting, third basin 

 shaped with second adherent. Borsal fin with some spinous rays. 



One family, the BatraoMda, 



III. Scyphobranchii. Basis oranii simple, no tube; posttemporal furcate. Superior pharyngeals shortened, fourth 

 and first generally wanting, third large, basin-shaped, second generally scale-like or coossifled with third. Scapula 

 with median foramen. Dorsal radii usually soft. Families Uranoncopidm, Gobiidus (genera Qobius PMlyjmus Mleoirn 



