TWO EXTINCT 2IA2niALS FROM TEXAS— HAY. 



113 



by fibro-cartilage ; hence there was some movement at this point of 

 the vertebral column. 



The whole congeries of vertebrae which compose the lumbosacral 

 tube is missing, except a fragment which appears to represent tlie 

 fourth and fifth sacrals, and another fragment which furnishes the 

 hinder part of the centrum of the seventh sacral and the whole of 

 the eight. To the latter is attached a large part of each lateral 

 process. On the front edge of each of these processes is a stump of 

 the lateral process of the seventh sacral. The hinder end of the 

 centrum of the eighth sacral, smooth for movable union with the 

 first caudal, has a width of 73 mm. and a height of 55 mm. 



There are present six caudal vertebrae. The average length of 

 these is 77 mm. These belong at the base of the tail and all bear 

 facets for chevrons. According to Burmeister's figure ^ and that of 

 Lydekker- the tail of Glyptodon has 11 vertebrae. Of the whole length 

 of the tail the basal six vertebrae occupy a little more than one-half. 

 It seems probable, therefore, that the tail of G. petaliferus had a 

 length of about 810 mm. An estimate indicates that our Texas 

 species had a length of head, body, and tail of about 7 feet. 



Both humeri are defective. The heads of both are present and 

 the distal ends of both ; but intervening portions are missing. It is, 

 therefore, impossible to determine with certainty the original length 

 of the bone. The humerus fig-ured by Burmeister^ as that of 

 Glyptodon asper may be taken for comparison. On the inner border 

 of the bone of the Texas specimen (pi. 3, fig. 9) there are, as in the 

 one just referred to, a pair of tuberosities. Assuming that these are 

 in the same relative positions in the tw^o species the total length of 

 the humerus of the Texas specimen will be 310 mm. The following 

 measurements are taken : 



Measurements of humeri of Glijpiodonts in miUimeters. 



It will be seen that the bone of the Texas species is slenderer than 

 in the other, both in relation to the total length and to the distance 

 of the inner tuberosities above the distal end. 



1 Anales Mus. Pub., Buenos Aires, vol. 2, pi. "'?,. 

 " Anales Mus. La Plata, vol. 3, 1894, pi. o. 

 = Anales Mus. Pub., Buenos Aires, vol. 2, pi. 32, fig, 2. 

 -Proc.N.M.vol.51— 16— 8 



