304 PATAGONIAN EXPEDITIONS : PALAEONTOLOGY. 



MEASUREMENTS. 



Ungual phalanx, digit IV, length 026 Femur, width of shaft above third tro- 



" " "V " 01 1 chanter 030 



Ungual, digit III, proximal width oio " thickness of shaft above third 



Femur, width of proximal end 056 trochanter 022 



SCHISMOTHERIUM SPLENDENS (Ameghino). 

 (Plate LI, Figs. 2-3*.) 



Metopotherium splendens Amegh. ; Rev. Argent, de Hist. Nat., T. I, 

 1891, p. 324. 



In the Brown collection, American Museum of Natural History, is a 

 representative of this species (No. 9,247) which agrees very well with the 

 type, and consists of a skull without mandible and lacking the cranial 

 roof, associated with the atlas, ulna and fibula. Another individual in the 

 Princeton Museum (No. 15,590, a skull lacking the occiput, basis cranii 

 and mandible, found by Mr. Peterson at Halliday's) is more aberrant, but 

 almost certainly referable to the same species. 



The dentition varies much in the different individuals, but, neverthe- 

 less, displays certain constant differences from that of S. fractum. The 

 upper caniniform (~) is small, recurved, of longitudinally elliptical section 

 and usually is obliquely worn, but in the Princeton specimen this tooth is 

 extremely small and protruded but little below the level of the alveolus, 

 and the exposed portion is not recurved, but straight and horizontally 

 abraded ; the great reduction of - in this individual is probably a sexual 

 character. The space between A and - almost deserves the name of an ex- 

 tremely short diastema and in all known examples is longer than in the 

 preceding species. The second upper tooth is styliform and may be sub- 

 trihedral or subquadrate in section ; the three succeeding teeth are trans- 

 versely oval, diminishing in size from ^ to *-, which is the smallest of the 

 molariform series. These teeth are broader and more antero-posteriorly 

 compressed than in S.fracttim, notably so in No. 9,247, in which this fea- 

 ture is exaggerated. In the subjoined table the measurements of the type 

 are, except in the case of - and -, taken from the empty alveoli. 



MEASUREMENTS. 



Type. No. 9,247. No. 15,590. 



Upper dentition, length 038 .038 .038 



" " " 2.-6. O3O .O3O .030 



-L, length (i. e., antero-posterior diameter) 005 .006 .004 



