NATURAL SCIENCES OF PHILADELPHIA. 235 



apparently subequal and bifurcated. Antepectoral region longitudinally ob- 

 long. Ventral tins small, inserted a short distance behind the pectorals, and 

 separated by the comparatively wide pubic bones. There are less than five 

 rays to each ventral, the number being apparently a spine and four rays, 

 which are simply articulated. 



This genus is nearly related to Aulorhynchus, but differs in the ossified 

 snout, which, like the crown, is corrugated, the structure of the jaws, the 

 lateral row of plates, the form of the dorsal spines and the presence of inter- 

 vening plates, and, finally, in the structure of the ventral fins and the arma- 

 ture of the pubic bones. The pectoral fins are mutilated, and it is therefore 

 difficult to decide whether their form was similar to those of Aulorhynchus, 

 but it is probable that such was the case, or that at least the inferior rays 

 were as long as those immediately above, and consequently the posterior 

 margins of the fins truncated. 



Aulichthys Japonicus, Brevoort. 



The snout forms 7-12ths of head's length, exceeds twice the height of the 

 body and is nearly l-7th of its length. 



B. 4. D. XXV. 8. A. I. 10. C. 5. 13. 4. P. 11. V. I. 4. Lat. line 52. 



Purplish brown, darker over tube, lighter on abdomen ; opercles silvery 

 iridescent ; humeral area bluish silvery, {Brevoort. ) 



Hibitat. Japanese coast. 



Remarks on the relations of the Genera and other groups of CUBAN FISHES. 



BY THEODORE GILL. 



My attention having been attracted to the fishes of the Island of Cuba and 

 some points in their classification and arrangement by the recent researches 

 of Prof. Poey and his correspondence, it is here proposed to offer some obser- 

 vations on the affinities of the genera and higher groups found in the waters 

 surrounding that island,* the groups being discussed in the order of M. Poey's 

 Conspectus. 



M. Poey's arrangement differs chiefly from that proposed in the "Catalogue 

 of the Fishes of the Eastern Coast of North America" by the precedence 

 given to the subclasses Elasmobranchii and Ganoids, and to the Teleostean 

 orders of Plectognathi and Lophobranchii. The distribution of the sharks 

 and rays among families has also been omitted, as well as the subdivisions 

 of families into subfamilies. 



Seven of the families of Squali are represented in Cuban waters. They 

 are the Galeorhinoidse, Cestraciontoidse, Lamnoidae, Alopecoidae, Notidanoidse, 

 Spinacoidae and Ginglymostomatoidse. The Squalus tiburo and S. acronotus 

 belong to the genus Isoplagiodon, Gill; the & platyodon, S. obtusus and S. longi- 

 manus to Eulamia. For the Oxyrhina glauca and its allies,! the genus Isu- 

 ropsis has been lately proposed. 



Of the Rays, five families are represented : 



The Plectognathi are rather numerous. The most interesting is the Hollar- 

 dia Hollardi, (Poey,) which is nearly allied to the Triacanthodes anomalus cf 

 Japan ; the two genera appear to belong to a peculiar subfamily (Triacantho- 

 dinae) of the family of Triacanthoidse. 



The Percoids of Cuba are represented by many genera, and may be dis- 

 tributed in the following manner : the subfamilies are only provisional ones. 



* I entertain doubts as to the validity of some of the species proposed by M. Poey, but 

 have generally preferred to leave to that learned gentleman the determination of such 

 doubtful species. 



t The species of Cuba is probably the same as the Isuropsis dehayi of our own 

 coast 



1862.] 



