Nalurol Sciences of Philadelphia dwing the Year 1824. 8.51 



Lesueur, whose exertions have furnished this year tliree in- 

 teresting memoirs, of which the two first deserve particular 

 notice ; the third is still in the hands of the Committee of Ex- 

 amination. They are entitled, 1st, " Description of two new 

 species of the genus Batrachoid of Lacepede." 2nd, " De- 

 scription of several species of the Linnaean genus Raia." 3i'd, 

 " Description of two new species of Blennius." The genus 

 Batrachoides, established by M. de Lacepede, has received 

 from Mr. Lesueur considerable modifications. He discards 

 from it the B. blennoidcs and B. Gmelini, included in it by 

 Lacepede and Risso, and restricts it to the B. Tau of authors, 

 the B. vernuella published by him in the Annales du Museum 

 d^Histoire Naturelle, and to the two new species which he de- 

 scribes in this memoir under the names of variegata and Die- 

 mensis; the latter of which was formerly collected by him on 

 VanDiemen's Land : the other has been recently found on our 

 coast. Besides making known these two species, Mr. Lesueur's 

 paper contains some general observations on the characters of 

 this genus, which has not yet received much attention from 

 naturalists, owing probably to the small number of species 

 known. 



The genus Raia, established by Linne, has been long since 

 split into many genera, to accommodate all the species that 

 were found to belong to it. The necessity of describing from 

 dried specimens has doubtless been the cause of much of the 

 uncertainty and confusion attending the descriptions given by 

 authors ot" the different species of Raia. Mr. Lesueur has 

 endeavoured to elucidate the point as far as relates to those of 

 our country. He describes four new species, under the names 

 of Raia Desmarestia, Raia Chantenay, Trygon Sabina, and 

 MyliobatisFreminvillii; and makes it probable that, if the de- 

 scriptions of Mr. Bosc are faithful, one additional species will 

 exist, which for the present he unites to the Raia eglantiera of 

 that author. Mr.Lesueur proceeds to describe an animal which, 

 under the various absurd appellations of Devil Fish, Wonder- 

 ful Sea Serpent, and Vampyre of the Ocean, had attracted 

 considerable attention, and had been exhibited in several of 

 our cities. He describes it as a Cephaloptera Giorna. This 

 is probably the same animal which Dr. Mitchill, of New York, 

 had described in the Annals of the Lyceum of Natural His- 

 tory of New York, imder the name o{ Cephalopterus Vampyrus. 

 After a number of practical observations on the Rays, ex- 

 hibiting an intimate acquaintance with his subject, and the 

 real value of which can be fully appretiated by those alone 

 who are conversant with ichthyology, Mr. Lesueur adds, " I 

 have adopted for this species the name of the celebrated Giorna, 



well 



