Cope.] 5oo lJan.5, 



place the genus in the Biatodonta, which has the carpus nearly that of the 

 Tdxeopoda, and the tarsus of the Diplarthra. The points of resemblance 

 to the Coiidylarthra are the following : The ilium is narrow. The humerus 

 has an epitrochlear canal. The superior molar teeth have but one internal 

 lobe. The resemblances to the Pantodonta are these : The cervical ver- 

 tebne are plane and short. The femur has a third trochanter. The pre- 

 maxillary bone in dentigerous. The astragalar trochlea is as in the 

 Periptychldce, and the ProbosrMia ; that is without groove, and slightly 

 convex anteroposteriorly, thus differing from that of the Pantodonta. The 

 dentition is especially like that of the Amblypoda in general, and that of 

 the superior series is unlike anything known in the Diplarthra. 



I propose to place this genus in the Amblypoda for the present, next to 

 the Pantodonta, but it cannot enter that sub-order on account of the form 

 of its astragalus. The sub-orders of Amblypoda will be defined as follows : 



Astragalus with a head distinct from trochlea, with distal ar- 

 ticular facets Talicjrada. 



Astragalus without head ; distal facets subinferior Pantodonta. 



In the sub-order Taligrada, the single family Pantolambdidce presents the 

 following characters : 



Superior and inferior molars with the cusps developed into Vs. Post- 

 glenoid process present ; postympanic and paroccipital not distinct. All 

 the vertebrae with plain articulations. Humeral condyles without inter- 

 trochlear ridge. Femur with third trochanter. Digits of posterior foot 

 probably five. Metapodial keels small and posterior. 



Of this family Pantolambda is as yet the only known genus. Its leading 

 characters are as follows : 



Canine teeth distinct ; dental series continuous. Superior molars all 

 triangular, that is with a single internal cusp. External cusps of premo- 

 lars unknown ; of molars two. Internal cusp V-shaped, sending its horns 

 externally as cingula to the anterior and posterior bases of the external 

 side of the crown, without intermediate tubercles. Inferior true molars 

 with a crown of two Vs, the anterior the more elevated. Premolars con- 

 sisting of one open V, with a short crest on a short heel, as in Coryphodon. 

 Dental formula I'| ; C. i ; P-m. l\; M. f ; the last inferior with a heel. 

 A strong sagittal crest. Auricular meatus widely open below. Large 

 postparietal, postsquamosal and mastoid foramina. 



Cervical vertebnu rather short ; other vertebra? moderate, the lumbars 

 not elongate. A large tail. Humerus with large internal epicondyle. 

 Femur with all the trochanters large. Ilium with the anterior inferior 

 spine well developed. Metacarpals short, plantigrade. Phalanges of second 

 series flat, and of subquadrate outline. The astragalus has a wide head, but 

 no neck, as it is not separated from the tochlear port ion hy a constriction. 

 It is as Avide as the trochlear portion, but about one -third of its length ex- 

 tends within the line of the malleolar face of the trochlear portion. The 



