658 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 57. 



PLATTGONUS VETUS Leidy. 



Type. — Portion of a palate containing most of the cheek-teeth 

 and a fragment of a lower jaw containing the last true molar. Pres- 

 ent location of type, Academy of Sciences, Philadelphia. 



Type locality. — Mifflin County, Pennsylvania. Described by 

 Leidy in 1889.^ 



Diagnosis. — A decidedly larger species than P. compressus ; total 

 length of cheek-tooth series about 97 mm.; upper molars 1 and 2 

 nearly as wide as long ; apparently no intermediary cusps or loph con- 

 necting anterior and posterior lobes of the molars. Other specific 

 characters not known. I provisionally refer to this species a single 

 specimen (Cat. No. 8917, U. S. N. M.), consisting of a portion of the 

 palate of a young individual, lacking the two last molars and carry- 

 ing the last two milk-molars of the right side. The teeth are about 

 the same size, the molars have the same proportion, and they appear 

 to agree in other respects with those of Leidy's type. 



Measurements of specimen No. 8917, referred to P. vetus. 



Length of premolar series 40 mm. 



Diameters in millimeters- ^stSr tI^s"'" 



p*. 12 12 



p' 12 13 



p* 12. 5 14-f 



dp* 12. 5 11. 5 



dp* 13 12. 5 



m' 16. 5 16. 3 



m' 20. 5 20 



Length of premolar series 40 mm. 



Length of cheek-tooth series, exclusive of m' 76 mm. 



Width of palate between second molars 22. 5 mm. 



, '^^' PLATTGONUS ALEMANI Dnges. 



Type. — Portions of a skeleton, including a palate fragment carry- 

 ing all the cheek-teeth; lower jaws (lacking only a portion of one 

 angle; the incisive border, the crowns of the canines, broken off, and 

 one premolar) ; the right hind foot (lacking only two phalanges) ; 

 and portions of a scapula, humerus, ulna, five cervical vertebrae and 

 a rib. This type, lacking the palate and scapula portions, is in the 

 U. S. National Museum (Cat. No. 791). 



Type locality. — Near Moroleon, Guanajuato, Mexico; about 200 

 miles northwest of the City of Mexico. Described by Dr. Alfredo 

 Duges, in 1887.^ 



Diagnosis. — A somewhat smaller species than P. vetus; total 

 length of upper cheek-tooth series (estimated) about 87 mm.^ It 



» Leidy. Proc. Acad. Nat Sci. Phila., 1883, p. 301 ; Ann. Rept. Penn. Geol. Surv. for 

 1887, 1889, pp. 12-14, pi. 2, figs. 1 and 2. 



^La Naturaleza, ser. 2, vol. 1, 1887 to 1890. Note, Dugfes' article is dated "Dec, 

 1883," but it Beems not to have been published until 1887. 



• This estimate is based on the actual length of the lower series which measures 90 mm. 

 In Platygonua the lower series exceeds the upper in length from 3 to 5 mm. 



