202 THE DESEADO FORMATION OF PATAGONIA 



pits, the median lateral plates with rudimentary piliferous 

 pits, and the dorsal ones with well marked posterior pits. 

 In each succeding row toward the rear, the plates are more 

 distinctly ornamented and have larger posterior marginal 

 pits. I have no marginal plates. 



The plates of the pelvic buckler do not overlap, are 

 shorter, have a very distinct figure, and, in addition to the 

 longitudinal furrows, have a couple of radial furrows on 

 either side, which divide the plate into four or five areas 

 (see fig. 132 a and b). 



The caudal vertebrae are short and thick, indicating a 

 short tail. I found no plates which would indicate a caudal 

 shield, which coincides with the experience among the 

 Santa Cruz specimens. The figures are to scale and give 

 most of the measurements. 



There are ten rows of movable plates, probably two to three rows lacking. 



There are twenty -f~ plates to a row. 



A typical movable plate measures 17 mm. long by 6 mm. wide. 



There were at least four rows in the pelvic buckler, probably eight as in the 



Santa Cruz. 

 A typical fixed plate measures 10 mm. long by 5 mm. wide. 



Prozaedius tenuissimus Ameghino 



P. tenuissimus Amegh., 1902, Bob Acad. Nac. Cienc. Cordoba, t. 17, p. 66. 



This species is characterized by Ameghino on account 

 of its small size. The movable plates have two furrows 

 which converge toward the front, and between which is a 

 median crest. In the furrows are two rows of perforations. 

 A movable plate measures 9 mm. long by 4 mm. wide. 



Stenotatus Ameghino 



Euphractus Ameghino, in part, 1887, Bob Mus. La Plata, t. I, p. 26 of separate. 



Dasypus Amegh., in part, 1889, Act. Acad. Nac. Cienc. Cordoba, t. 5, p. 864. 



Stenotatus Amegh., 1891, Kevista Argen. Hist. Nat., t. 1, p. 253. 



Dasypus Lydekker, 1894, Anal. Mus. La Plata, t. 3, p. 55. 



Prodasypus Amegh., 1894, Bob Acad. Nac. Cienc. Cordoba, t. 13, p. 172 of 



separate. 

 Stenotatus Scott, 1903-5 Princeton Patagonian Expcd., vol. 5, p. 80. 



The genus is very like Prozaedius but differs in having 

 thicker and wider movable plates, in having more rows of 



