104 PATAGONIAN EXPEDITIONS: PAL/EONTOLOGY. 



cephalic shield. This plate is relatively broader than in the two preced- 

 ing species, the breadth exceeding the length. A specimen in the 

 Ameghino collection yields the following measurements : length, 40 mm., 

 breadth of posterior border, 45.5 mm., breadth of anterior border 22 mm. 

 The exposed surface of the plate is very rough and coarsely pitted, with 

 large irregular depressions ; it has no such raised border as in P. strepens 

 and P. ferox, except a slight indication of it on the sides. 



In the original account of this species by Moreno and Mercerat an ele- 

 ment of confusion was introduced by describing as T, which is very 

 small in all the species. 



PELTEPHILUS NANUS Ameghino. 



Peltephilus nanus Amegh.; Secundo Censo d. Repub. Arg., 1898, p. 220. 



Very little is known of this species, but the scutes of the carapace 

 justify its reference to the present genus, while the extremely small size 

 (the femur is only 62 mm. long) indicates its specific distinctness. 



? PELTEPHILUS RARUS Ameghino. 



Anantiosodon rants Amegh.; Rev. Arg. d. Hist. Nat, T. I, 1891, p. 327. 



Ameghino's original description of this species and supposed genus is 

 as follows: "Represented by a piece of the right mandibular ramus, 

 with part of the symphysis ; the ramus is delicate and has its ventral 

 border turned inward for its whole length ; the symphysis is narrow and 

 rounded. In the ramus are not more than four compressed teeth, with 

 major diameter somewhat oblique and with structure apparently like that 

 of the Dasypoda. The whole piece is strongly curved. Length of space 

 occupied by the four teeth, 18 mm., depth of jaw below teeth, 10 mm." 



The type-specimen is a very unsatisfactory fragment, from which little 

 can be learned. It is probably referable to Peltephilus, perhaps even to 

 some of the preceding species, but its determination must await the dis- 

 covery of better material. 



GENERA INCERT^E SEDIS. 



Ameghino has named two other genera of Santa Cruz armadillos, Prccn- 

 phnictns and l^ete/ia, concerning which I can add nothing to what he has 

 already published. I shall therefore merely give the literature dealing 

 with these doubtful forms. 



