50 Bibliographical Notices. 



4. ' On Stinging Organs of the Medusa, and the occurrence of 

 peculiar formations in Evertebrate Animals, which appear to consti- 

 tute a new class of locomotive organs,' by Rud. Wagner. 



5. * Zoological Notices,' by Dr. A. Philippi. These we shall 

 subsequently give in continuation of those which have already ap- 

 peared in the ' Annals.' We will now enumerate the various heads : 

 1. Fossarus, a new genus of Mollusks. 2. On the genus Eulima, 

 Risso. 3. On the genus Truncatella, Risso. 4. On Tornatella. 5. 

 Onchidium nanum, n. sp. 6. Euplocamus laciniosus, n. sp. 



6. ' Contributions to a systematical knowledge of the Larvae of In- 

 sects,' by Dr. Erichson. 1st part : The Larvae of the Coleoptera. 



7. ' Grouping of the Genera of the Rodentia into Natural Fami- 

 lies, with descriptions of some new Genera and Species,' by Prof. A. 

 Wagner. The first part of this paper consists of a review of the 

 literature on this subject, in which great praise is bestowed on the 

 labours of Mr. Waterhouse*, to whose classification, however, it is 

 objected, that not all families are reduced to their proper limits, and 

 that some have been discarded which must be re-established. The 

 author divides the Rodentia into twelve families, founded not merely 

 on external habits, but chiefly on the structure of the skeleton and 

 the dentition ; in some cases the intestines have likewise been con- 

 sulted. 



I. Pedimana. Digiti anteriores longissimi, pedes posteriores pol- 



lice instructi ; cranium rotundatum, orbitae postice clausae. 

 Only one genus belongs here, Cheiromys. Hab. Madagascar. 



II. Sciurina. Pedes anteriores digitis 4 et verruca hallucari, 



posteriores 5-dactyli, cauda dense pilosa ; dentes molares 4 ; 

 ossa frontalia dilatata, processu postorbitali distincto instructa ; 

 foramen infraorbital angustissimum. 

 Genera : Sciurus, Pteromys, Tamias, Spermophilus, Arctomys. 

 This family is represented in all parts of the world with the ex- 

 ception of New Holland. 



III. Myoxina. Pedes anteriores digitis 4 et verruca hallucari, pos- 

 teriores 5-dactyli, cauda elongata villosa ; dentes molares f , 

 ossa frontalia valde coarctata, processu postorbitali privata ; in- 

 testinum caecum nullum. 



M. Wagner has separated the only genus of which this family 

 consists into the four sub-genera, Graphiurus, Eliomys, Glis and 

 Muscardinus. Geographical distribution confined to the Old World. 



* Mr. Waterhouse's paper, ' Observations on the Rodentia,' &c. Mag. Nat. 

 Hist. 1839, pp. 90, 184, 274 and 593 ; and ' On the geographical distribution 

 of the Rodentia,' Annals of Nat. Hist. No. 33. (1840) p. 418 ; and Proc. 

 Zool. Soc. for Nov. 1839 ; see also ' Observations on the skulls of the Ca- 

 viida and Chinchillidce,' Proc. Zool. Soc, April 1839, and ' Observations on 

 various Rodents in the Zoology of the Voyage of the Beagle.' 



