Bibliographical Notices^ AQQi;^ 



Malapterurus electncus, a Siluroid fish inhabiting the Nile, and the 

 Gymnotus electricus, or Electrical Eel of South America. Similar 

 organs have also been attributed to three other fishes, but their ex- 

 istence has not been proved. These are the Trichiurus electricus, 

 Tetraodon electricus, and Rhinobatus electricus. 



The author then passes in review the various opinions which have 

 from time to time been put forth as to the possession of electrical 

 properties by the various species of Rays ; the evidence existing on 

 the subject being, in his opinion, insufficient to establish the fact of 

 the existence of such properties, although the matter may still be 

 regarded as doubtful. He then proceeds to some general observa- 

 tions on the history of this branch of Ichthyology, and afterwards 

 passes to the description of the electrical organs of the Torpedo, aud 

 of those parts of its anatomy which appear to be immediately con- 

 nected therewith ; the details of this description are for the most 

 part derived from M. Sa\i's paper on the same subject. Then follow 

 descriptions of the genera and species. Of this part of the work the 

 following is an abstract : — 



Family TorpedinidjE (Torpediniens) . 



Body discoid, flat, rounded, smooth and naked ; tail short, fleshy ; 

 ventral fins (catopes) immediately behind the pectorals {pleuropes) ; 

 dorsal fins {epiptera) one or two, or entirely wanting ; nasal valvules 

 united to form a single lobe, with its margin free ; teeth pointed ; 

 possessing an electrical apparatus. 



This family, according to M. Dumeril, contains five genera, of 

 which one is here described for the first time. Of these he gives the 

 following synoptical table : — 



("eyes distant ftom the spiracula 1. Torpedo. 



f with two eyes J , . .^ ■ f^l' 'i""^" "'*" o m ■ 



^ eyesclose to the spira-J the disc 2. Narcme. 



fdi8tinct< 1 cula Suilveryshort... 3. Hypnos 



Uorsalfins J 1 >- L ("• S-)- 



or epiptera I L with but one eye *• Astrape. 



(.wanting _.„ ~ - 5. Temera. 



Genus 1. Torpedo, Dumeril. 



To this genus M. Dumeril refers seven species, of which he gives 

 the following tabular arrangement : — 



Jventra'is f dorsal fins large 2. T. marmorata, iJ/jjo. 

 elliptical! dorsal fins small 3. T. trepidans, Vol. 



hoco nf ta.n (T. hebetans, Xouw?) 



fvlry broad L'enfals circular 4. T. pantbeta, E/iren6. 



r more or I . 1st dorsal broad Tspiracula an- 



less or-' and rounded I nular 1. T. oculata, &ton. 



' f 1st dorsal broad Tspiracula an- 



V,.- and rounded J nular 



u.sc , biculaV. I baseoftaila' | spiracula reni. 



"'"^ <. little nar- I L form 6. T. Nobiliana, Bonap. 



^ rowed \lA dorsal long and tapering ... 5. T. Siniis Persici, KUmpf. 

 Uearly quadrangular 7. T. occidentalis, Storer. 



Genus 2. Narcine, Henle. 



This genus also contains seven species, of which four are described 

 as new. M. Dume'ril does not seem to be aware of the two species 

 of this genus described by Sir John Richardson in the British Asso- 



