1820.] Physical Science during the Year 1819. 107 



of the true genus Esox (pike); six species of Pimelodes; one 

 of AciPENSER (sturgeon); and two of MoLVA. 



In the Memoires du Museum, Cuvier has described six new 

 species of Salmomd.e, which he refers to three new genera : 

 1 Myi.etes, having prismatic teeth. This genus contains six 

 species, which belong to two divisions ; the first with their belly 

 acute • the second with that part rounded. 2. Chalcjeus, hav- 

 ing teeth short and round. 3. Tetuagnopterus, a genus 

 before given by Artidi, in Seba's Thesaurus. 



Rafinesque has hkewise given, in the Journal of the Academy 

 of Philadelphia, a new genus of the family Spaiiid^, named 

 PoMOXis; another, Sarchirus, belonging to the family 

 Esocide; and Exoglossum, referable to the CvPRiNiDiE. 



A new genus of the family CvPRiNiDiE, having appendages 

 in the mouth and abdominal fins, has been observed by Rafi- 

 nesque, who named it Hemiplus, and has described one 



species. „ , 



In the same number of the Annals of JNature, we tiiid 

 described two new species of Cyprinus, andone of Salmo. 



Type II, ANNULOSA. 



Class I, Vermes. 

 Four new species of Hirudo are published by Rafinesque m 

 his Annals of Nature, No. I. 



Class II, Chetopoda. 



Blainville has written a very excellent paper on the classifica- 

 tion of these animals, in the Bulletin des Sciences ; and has 

 named the class Chetopoda which he formerly designated 

 Setopoda. 



We are happy to have it in our power to state that the cele- 

 brated Savigny "is soon about to print a work on this class of 

 animals. 



Class III, Myriapoda. 



Some new genera and species of this class are described by 

 Rafinesque in No. I. of his Annals of Nature. 



Of the first order, we find a genus Selista, allied to the 

 LiTHOBUis, of which he has found one species. Of Cuypto- 

 mera another new genus, aUied to Polydesmus ; two species 

 are given. Of Stenomera, anew genus allied to Crypto 

 MERA, one species is described. Of MYcoTiiiniES, the author 

 says, there are several species, three of which only are described.- 



Of the second order we find four new genera, viz. 1. Pleu- 

 ROLOMA, aUiedto Gi.omekis. 2. Narceus, allied to Julus. 



3. RllEXENOR. 4. AUACION. 



Class IV, Insecta. 

 A very learned work, entitled " Horai Entomologies," Part I, 

 on the classification and distribution of the insects composing 



