de figuras periféricas pequeñas, en número de nueve, de tamaño des- 

 igual, todas de superficie plana y casi lisa, separadas entre sí por 

 surcos bien marcados pero poco profundos. En el surco que rodea la 

 figura central existe un cierto número de perforaciones. 



Las diferencias que distinguen a esta especie son muy difíciles de ex- 

 plicar por medio de palabras, pero saltan inmediatamente a la vista 

 cuando se examinan las piezas originales. 



Procedencia: — Barrancas de los alrededores de la ciudad del Paraná. 



Horizonte: — Piso mesopotámico de la formación patagónica (oligo- 

 ceno inferior). 



lIoiM.oriinuus (?) I,y!)i;kkehí, m. s¡'. 



Lm»1»h L.\.\X1V. ñgurn s 



Hniilofhonis <•), sp. r. Lyuekker: Cat„t. vf thc Fossil Mamm.. iii Ihc Biili.-li Musciim, 

 paite V. página 133. figura -m. iSS;. 



Esta especie está representada en el Museo Británico por la extre- 

 midad de un tubo caudal y un trozo de la parte anterior de la coraza, 

 caracterizándola Lydekker en los siguientes términos: 



The folloii'ing specimens indícate a species apparently nearly or quite 

 as large as Glyptodon reticulatus. The large terminal disks on the lateral 

 surfaces of the tiibe of the caudal sheath are separated froin one another 

 hy a roiv of small disks, and are followed laterally by a series of enlar- 

 ged disks, which decrease gradually in size as they reced from the tip. 

 The disks on the dorsal aspect of the tube are subcircular in shape, fre- 

 quently concave, and present great variation in size, but those on thir 

 ventral surface are more regular in this respect. The scutes of the frag- 

 ment of carapace are oblong, ivith the grooves very indistinctly marked. 

 and with a series of hair-pits in the groove surraunding the central disk. 



Although the present form is aparently distinct from all described 

 species, with the exception of the so-called Glyptodon clavipes of Bur- 

 r.ieister, the writer thinks it inexpedient at present to assign to it a dis- 

 tinct specific ñame. 



The extremity cf the terminal tube of the caudal sheath; from the Pleis- 

 tccene of Uruguay. This specimen, although of considerable larger size, 

 apparently agrees very closely with the terminal tube figured by Bur- 

 meister, under the ñame of Glyptodon clavipes, in the «Anales del Mu- 

 seo de Buenos Aires^, vol. II, pl. XL, figs. 7, 8, showing the irregular 

 arrangement of the disks on the ventral surface (fig. 7), and the large 

 sub-circular lateral ones (fig. 8), which decrease regulary in size from 

 the hindmost one. In the terminal tube of a caudal sheath referred by 

 Oiven to Glyptodon clavipes, but which, as already mentioned, probably 



