128 EDENTATA. 



18936. The distal extremity of the right humerus of an equal-sized 

 but different species of Hoplophorus. This bone differs 

 considerably in form from the corresponding portion of 

 the last specimen, the entepicondylar foramen being oval 

 instead of nearly circular. 



18648. The right astragalus. This specimen agrees in size with the 

 corresponding bone of H. ornatus. 



18648 a. The left astragalus. 



18941 a. The left half of the conjoint centra and part of the 

 neural arches of the axis and three following vertebra?. 

 This specimen agrees very closely with the corresponding 

 element figured by Lund in the ' K. Danske Vid. Selsk. 

 Skr.' vol. ix. pi. xxxv. fig. 1, under the name of H. 

 euphractus ; and from its resemblance to the vertebras of 

 H. ornatus figured by Burmeister in the ' An. Mus. Buenos 

 Aires,' vol. ii. pi. xix. fig. 6, may perhaps belong to the 

 present species. 



Koplophorus ornatus (Owen ' ). 



Syn. Qlyptodon ornatus, Owen 2 . 



Hoplophorus lurmeisteri, Ameghino 3 . 



Since there may possibly be a doubt as to the identity of the 

 complete carapace figured by Burmeister in the ' An. Mus. Buenos 

 Aires ' under the present name with the fragment to which the name 

 G. ornatus was applied, it will be advisable to regard the former as 

 the type. 



The features distinguishing this species are the depression of the 

 central disks of the scutes of the carapace, and the smooth surface 

 of the disks. There are usually from eight to ten or twelve 

 peripheral disks in each scute, which are always separated from the 

 disks of the adjacent scutes by shallow grooves. In the middle of 

 the dorsal region the central disk of each scute is but slightly larger 

 than the peripheral ones, but in the lateral region the central disk 

 becomes very much larger. The carapace is elongated in form, its 

 total length being about four feet. The disks on the dorsal aspect 

 of the terminal tube of the caudal sheath are often oval, convex, 

 subequal in size, and regularly arranged ; the hinder lateral disks 

 being saddle-shaped. 



Bab. South America (Argentine Republic). 



1 Cat. Foss. Mamm. Avea Mus. R. Coll. Surg. p. 119 (1845). Glyptodon. 



Loc. tit. 



9 Quoted in the Bol. Ac. Nac. Cordova, vol. v. p. 32 (1883). 



