PARASTRAPOTHERIUM 145 



pit. Behind the posterior lobe is a small basin, bounded 

 in the rear by a second crista from the rear end of the 

 external wall, which, as the tooth is worn down, unites 

 with the posterior lobes, cutting off a small posterior pit, 

 suggestive of that of homalodontotheres. 



The three lower incisors are expanded at their ends into 

 thick shovel-like crowns, each with a strong crescentic 

 cingulum on the posterior face, and with a shallow furrow 

 on both the front and back faces. Relatively the incisors 

 are much larger and longer than in Astropotherium. 



The lower canine is flattened on the upper face, so that 

 its cross section is close to semicircular making a typical 

 permanently growing rooting implement. This tooth is 

 relatively shorter and smaller than in Astrapotherium. 



Premolars I and 2 are wanting, a long diastema occupy- 

 ing the interval between the canine and pm. 3. Premolar 

 3 is greatly reduced in size, and in my specimen has fallen 

 out, being represented by a small alveolus. I judge that 

 in old individuals it falls out. The fourth premolar and 

 the molars are typically those of Toxodontia. The young 

 show two plump crescents, with a low plump pillar, sit- 

 uated near the anterior horn of the posterior crescent, 

 which pillar, as the tooth wears, unites with the anterior 

 horn. 



The scapula is a remarkably heavy and elongated bone, 

 greatly arched where it lay over the ribs. The spine is 

 high and heavy, with the upper margin developed into 

 a thick ridge like a banister rail, which is prolonged in 

 front to, or a little beyond, the level of the glenoid fossa, 

 this distal portion being expanded into a broad plate more 

 than half as wide as the widest portion of the blade of the 

 scapula. The glenoid fossa is relatively small, oval in 

 outline, and with the long axis parallel to the long axis 

 of the body. The anterior margin of the articular surface 

 is reflexed, apparently to come in contact with the base of 

 the greater tuberosity of the humerus. This glenoid cavity 



