392 Mr. O. Thomas on 



the Chih-Argentuie Frontier Commission, and presented by 

 Sir Thomas Holdich. 



This otter occurs side by side with L. felina along the 

 coasts of Southern Chili and in the Straits of Magellan, 

 where it was first obtained during the voyage of the ' Chal- 

 lenger,' and later on in the same region by Dr. Coppinger 

 of H.M.S. ' Alert.' I have long doubted my provisional 

 reference of it to L. jylatensis, from which I now hnd it can 

 always be distinguished by the different structure of its nose- 

 pad and the flattening of its muzzle, with the consequent 

 alteration in the form of tlie nasal opening in the skull. 



4. Lutra platensis, Waterli. 



Voy. Beagle, Mamm. p. 21, pi. xxxv. fig. 4 (skull) (1838). (Maldonado, 



Uruguay.) 

 Lufra solitaria, Wagn. Arch, f . Nat. 1842, p. 358. (Ypanema, Sao 



Paulo.) 

 Lutra latifrons, Nehr. SB. Ges. nat. Berl. 1887, p. 23. (" S. America, 



east of Andes.") 



Nose-pad naked, its upper line of demarcation running 

 either straight across or even curving somewhat downwards 

 towards the septum, its definition always sharp and well 

 marked. 



Skull larger and well ridged, not unusually flattened. 

 Nasal opening comparatively narrow, its breadth distinctly 

 less than its interior height-length diameter. BulltB well 

 swollen, p^ large, with broadly expanded inner lobe. 



In an old male the skiill-measurements are : condylo-basal 

 length 114'5 mm.; mastoid breadth 72*5; antero-posterior 

 diameter of p* 12"5. 



Hah. Southern Brazil, Uruguay, and Argentina ; inland 

 to Matto Grosso. Examples in Museum from Rio Grande 

 do Sul {Ihering), Uruguay {Darwin.^ Aplin), and Buenos 

 Ayres {Lord Lilford). 



Type skull in British Museum, no. 55. 12. 26. 215. 



5. Lutra incarum, sp. n. 



Nose-pad ill-defined, the hairy part from above projecting 

 downwards in the middle without any very clear line of 

 demarcation, and in some cases almost or quite meeting a 

 corresponding upward projection from below. There is, 

 however, never a broad continuous band of hair down the 

 septum as there is in L. enudris. In old specimens a good 

 deal of the hair may be worn off, but traces of it are to be 

 seen with a lens. 



