Marine Animal Forms in Fresh Water. 51 



fi'csh waters of Northern and Central Europe. That, on the 

 contrary, several speeies of Bleanius oeeiu* in the fresh waters of 

 Southern Europe, has been ah-eady observed ; the family of the 

 Gobioidei includes numerous East Indian freshwater fishes, se- 

 veral belonging to the genus Gubius itself. As regards Fala- 

 mon, a freshwater crustacean (' Camaron de agua dolee/ Palte- 

 niun Jainaicensis, A.) of Jamaica and Cuba has been known since 

 the time of Sloane and Parra ; and, according to an oral state- 

 ment of Dr.Engelmann,a species of this genus (still undescribed?) 

 lives near St. Louis in X. America. To the same family belong 

 the Sicilian Si/mei/tus Jluviati/is of llafincsquc, which, although 

 80 imperfectly described and again denied, rests upon some 

 observation, and also the Hippolyte Desmarestii of ^lillet, dis- 

 covered some time since in the Mayenne, the Sarthc and other 

 rivers of the north-west of France*; Dana's Cliilian freshwater 

 cv\iiit'dcea.n,Cri/p/iiups spinulosomanus ; and lastly, the pale, eye-less 

 Cavern Shrimp [Troglocaris) of the Adelsberg caves. Associated 

 with the latter is the recently-discovered Monolistra; this has 

 hitherto been the sole known freshwater representative of the 

 Jsopodes nageurs of Milne-Edwards {Cymothoidea, Dana), to which 

 Splueroma belongs. 



Several families also, which, even in the region of the ]Mediter- 

 ranean as in the North Sea, are purely marine, — of which the most 

 remarkable examples are the Scomberoidea, and Sharks and Rays, 

 — are represented in tropical regions by freshwater forms [Mono- 

 cirrhus polijacanthits, Heekel, in the Rio Negro; Carcharias 

 ganyeticus, Miill. & Henle, sixty leagues above the sea; Pristis 

 Perrotcti, Miill. & Henlc, in the Senegal ; Raia jiuviatilis, llam.- 

 Buch., near Kampur, 1000 English miles above the influence of 

 the tide; and the Trygon discovered by Schomburgk in the 

 River Magdalena). The entire section of the Rrachyurous 



Fishes and Crustacea of the Italian Fresh Waters," the occurrence of a 

 Bleuny in which was pointed out by PoHini as long ago as 181 fi. The 

 most important species observed by the author were — 



Atlterina lacustris, Bonap. 



Blennius vulyaris, Pollini. 



Gobiiis Jiuviatilis, Bonelli. 



Leiiciscus alburnellus. Fili])pi. 



Jjeuciscus Savignyi, Val. 



Alosafinta, Troschel. 



PaltB/non lacustris, n. sp., in the Lake of Albano. 



Spheeroma fossarum, n. sp., in the Pontine Marshes. 



Tliese species are all described in the second part of his memoir, and both 

 this and the first part contain remarks upon other animals inhabiting the 

 fresh waters of the South of Europe, which belong to what are generally 

 regarded as marine eroups. — Trans l.] 

 • Ann. Sci. Nat. xxv. pi. 10. fig. B. 1832. 



4* 



