. The Deseado formation of Patagonia . , 1897, Bol. Inst. Geog. Argen., t. 18, p. 450. The genus, in general, is similar to Astrapotherium, sothat Gaudry considered it the same, but Ameghino hasdistinguished it by the tushes being relatively of smallersize, the lower incisors larger, and by the presence of pm. 3 144 THE DESEADO FORMATION OF PATAGONIA in the lower series. The Deseado forms are also of con-siderably larger size than the Santa Ouz. Our material includes a pair of lower jaws, two scap-ulae, the humerus, and the lower end of the femur. No skull has been found in the Deseado. Those
. The Deseado formation of Patagonia . , 1897, Bol. Inst. Geog. Argen., t. 18, p. 450. The genus, in general, is similar to Astrapotherium, sothat Gaudry considered it the same, but Ameghino hasdistinguished it by the tushes being relatively of smallersize, the lower incisors larger, and by the presence of pm. 3 144 THE DESEADO FORMATION OF PATAGONIA in the lower series. The Deseado forms are also of con-siderably larger size than the Santa Ouz. Our material includes a pair of lower jaws, two scap-ulae, the humerus, and the lower end of the femur. No skull has been found in the Deseado. Those fromthe Santa Cruz are enormously swollen over the orbits,the massive bone making a skull wholly imique. Thelower jaws an> similar to those of Astrapothcrinm, exceptthat the rami are deeper. The front ends are fused andexpanded making the anterior much enlarged, and causingthe incisors to stand at intervals as in Corypliodon. Thesymphysis is massive and prolonged backward nearly topremolar 3. The rami are plump and unusually Kig. 102. Upper dentition of Astrapothcricuhis ilieringi—1/2 natural size. Of the upper dentition, Ameghino figures only the firstmolar and the canine. I have given Ameghinos figureof the upper dentition of Aslrapothericuhis, to indicatewhat this would be like, for the variation is only canine is a great tush, not unlike the incisor-tush ofPyrotherium, oval in cross section with the greater diameterfrom front to back. The first and second premolars havedisappeared. Premolars 3 and 4 are greatly molars arc very like those of Asmodeiis, large brachy-dont grinders, composed of an outer wall, and an anteriorand posterior lobe. The external cingulum is a traceonly, and the internal cingulum is developed in varyingdegrees. The basin is deep and subdivided by a cristawhich rises from the external wall, and as the surface isworn off unites with the anterior lobe, cutting off a small PARASTRAPOTHERIUM 145 pit. Behind the posterior
Size: 2632px × 950px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpub, booksubjectpaleontology
