432 PATAGONIAN EXPEDITIONS: PALAEONTOLOGY. 



MEASUREMENTS. 



No. No. No. No. 



Type. 959 6 - 9597- 959 8 - 9 6o - 

 Length, posterior border of median incisor 



alveolus to My inclusive . . . .014 .014 



Length of space occupied by vestigial teeth 



and posterior premolar .... .005 .005 



Length of inferior molar series on alveolar 



border . . .... .009 .009 .009 



Posterior premolar, antero-posterior diameter .0014 .0015 .0015 .0015 



" " transverse " .001 .001 .001 



MJ-, antero-posterior diameter . . . .0035 -0035 -0035 .0035 -3S 



" transverse " .002 .002 .002 



Mj, antero-posterior " .0025 .0025 .0025 .0025 .0025 



" transverse " .002 .002 .002 .002 



My, antero-posterior " .002 .002 .002 .002 



" transverse " .0015 .0015 .0015 



My, antero-posterior " .0012 



Depth of mandible below posterior premolar . .0035 -0035 



" " " " Mj . . . .0035 .0035 .004 .0035 .004 



" " " " M T .004 



PAL^EOTHENTES MINUTUS Ameghino. 



(Plates LXIII, Figs, i, 4-5*; LXIV, Fig. 2.) 



Palceothentes minutus Amegh. ; Enum. Sist. Especies Mamif. F6s. Pata- 

 gonia Austral., p. 6, 1887. 

 Epanorthus minutus Amegh.; Contrib. al Conocimiento Mamif. F6s. Rep. 



Argent, p. 274, PI. i, Figs. i6-i6a, 1889. 

 Paraepanorthus mimitus Amegh. ; Enum. Syn., etc., pp. 94-95, Fig. 40, 



1894; Bol. Acad. Cordoba, p. 350, Fig. 40, 1894. 

 Epanorthiis simplex Amegh. ; Enum. Syn., pp. 91-92, 1894 ; Bol. Acad. 



Cordoba, p. 347, 1894. 



Incomplete lower jaws of six individuals from Killik Aike (Nos. 15,706- 

 15,709, 15,068, 15,624) have been identified as belonging to this little di- 

 protodont. A maxillary fragment retaining the posterior premolar and the 

 molars is associated with one of the mandibles (No. 15,709). Two upper 

 molars (No. 15,999) collected by Mr. Hatcher on the south side of the 

 Santa Cruz River, sixty miles below Lake Argentina, and part of a left 

 mandibular ramus (No. 9122 American Museum) from a locality on the 

 Rio Gallegos, are also referable to this species. 



