102 Mr. Brookes on a new Genus of the Order Rodentia. 



quadrupeds which use their paws for the purpose of hands de- 

 pending in a great measure for the extent to which they can be 

 so employed, on the perfection or deficiency of these bones, and 

 on the rotatory motion of the radius on the ulna. 



With the generic character, and with a few observations on 

 the single species on which it is founded, I shall now conclude 

 this paper. 



LAGOSTOMUS. 



Denies incisores in utrdque maxiM duo elongati, prominentes ; 

 maxillae inferioris canaliculati, paul6 longiores. 



molares in utrdque maxilld utrinque quatuor, obliqui, 



antrorsilm extrorsilmque spectantes, coron4 simplici lami- 

 nate ; maxillai inferioris obliquiores bilaminati ; maxillae 

 superioris tres anteriores bilaminati, posticus trilaminatus. 



Pedes antici breviores, digitis quatuor. 



postici elongati, validi, digitis tribus : ossa metatarsi digitis 



numero aequalia. 



Cauda mediocris, pilis longioribus pectinatis vestita. 



Species unica. 



Lagostomus trichodactylus. 

 Tab. IX. 



Dipus maximus. De Blainville. F. Cuvier, Diet, des Scien. 

 Nat. xviii. p. 471. 



To the original descriptions given from the living animal by 

 M. de Blainville and by M. F. Cuvier it is necessary for me to 

 add but little, their general correctness being shown by a refe- 

 rence to the stuffed skin. I have ventured to change the trivial 

 name, as we are at present unacquainted with any congener with 

 which a comparison could be made, and it would be improper 

 to retain the epithet maximus for a single species. That which I 



have 



