310 Mr. 0. Thomas on Agoutis. 



XXXV. — Notes on Agoutis, loith Descriptions of new Forms. 

 By Olufield Thomas. 



(Publislied by permission of tlie Trustees of the British Museum.) 



In his list of duplicates for sale* Lichtenstein described, in 

 1823, an agouti as follows : — " Dasyprocta Azarse n. Acouti 

 Azar. Differt a Cav. Aguti Auct. potissimnm tergo concohre, 



j>ilis basi athis vestito. E provincia San. Paulo iirasil 



E. (i. e. specimen e.vimium) Tlilr. 7." 



lie here describes a specimen with a definite locality — Sao 

 Paulo, — and it is clear that the name must be applied to the 

 species of that locality, with his specimen as type, whether 

 the " Acouti " of Azara is or is not of the same species. 



In 1841, however, Lund t, finding that the Lagoa Santa 

 agouti was larger than the Paraguayan, with a longer tail, 

 described the former as new under the name of D. caudata, 

 and apj)lied the name D. azara to the latter. 



This allocation of names has been followed by Waterhouse 

 and other authors to the present time, though the distinction 

 of the two forms has not been generally recognized. 



Now, however, I find that the two species are undoubtedly 

 distinct, and since the name D. azarce must certainly be 

 applied to the Sao Paulo animal, with D. caudata as a 

 synonym, the Paraguayan one is left without a name. 



It may be called 



Dasyprocta f el icia, sp. n. 



Size decidedly less tlian in D. azarce. Colour on the whole 

 as in that animal, but the yellow of the fore-back and flanks 

 is paler and greyer, so that there is less contrast between 

 these parts and the greyish rump. Under surface with a 

 distinct mesial line of yellow or white running from chest to 

 inguinal region. Tail shorter than in azarce, little more than 

 ^ inch in length. 



Skull conspicuously smaller than that of D. azarce. 



Dimensions of the type (measured on skin) : — 



Head and body 490 mm. ; tail 15 ; hind foot 100 ; 

 car 84. 



Skull : greatest length 102 ; condylo-incisive length 86'4 ; 



* Verz. Doiihl. p. 8 (1823). 



t K. Dauslc. Vid. Sel^k. viii. p. 287 (1841). 



