Classification of the Order (htario]>hi/si. 27) 



Family 1. Rhamphichthyidze. 



The genu? R/nitn/i/iic/it/ii/s inclmU'.s (i.slie.s with a produced 

 snout and toolhlcs.s mouth, mental vent and anal fin origi- 

 nating below or in advance of the eyes. The ])ectoral arch is 

 more primitive in structure than in any other fishes oi" the 

 group. The small capsule which contains the anterior 

 })ortion of the air-bladder has a median aperture poste- 

 riirly, and there is on each side an antero-superior opening 

 which receives the end of the tripi/s. The vertebrae are 

 numerous (more than 140 in R. rostratux) ; the skull is very 

 •similar to that of Sternojyygus, with the fontanel very large. 



Family 2. SternarcMdas. 



The Sternarchinje include the genera Sternarchus, Stern- 

 archogiton, Sternarcliorhomphun, and Stemarchorhynchuf!, 

 In this subfamily the jaws are usually toothed, but the palate 

 is toothless. I have examined the skeleton in Sto.r iiarcJius 

 aUufroiis, which has the skull smooth and rounded and the 

 fontanel very small ; the orbitosphenoid is paired, the two 

 bones being separately united to the parasphenoid ; the 

 vertebrge number about 70. 



I have satisfied myself by dissection tiiat the pectoral arch 

 is precisely similar in structure in Sternarchus, Sterno/n/gus, 

 and Sleatogenys, differing from that of Rliamphiciithi/s in the 

 suialier size of tlie hypocoracoid and the absence of a meso- 

 coracoid. 



Sternopygas and 8te.atogi.nys agree together and differ from 

 the SternarchinEe in the absence of adipose and caudal fins 

 and in the structure of the skull, the fontanel extending from 

 supra-occipital to ethmoid, and of the mouth, a nodule of 

 cartilage intervening batvveen vomer and maxillary. In 

 Sternopygas teeth are present in the jaws and on the meso- 

 pterygoifls, in Steotogenys the moutii is toothless. These 

 two genera, with the allied Eigenniannia and IlypopomuSj 

 constitute the subfamily 8terno|jygin;i^. In Stemvpygus 

 macrurus there are more than 90 vertebne. 



Family 3. Gymnotidae. 



This family includes but a single species, Gyninotus carapo 

 [Garapus fasciatus), in most of its characters nearer to 

 Electrophorus than to the members of the preceding group. 

 'I'he skull approaches that of Electrophorus in general form ; 

 especially noteworthy is the curving upwards of the edges ol' 



