4376 University of California Publications in Geology [Vol. ll 



PAGE 



Equidae 472 



Hypohippus, near affinis (Leidy) 472 



Parahippus? mourningi Merriam 475 



Merychippus Leidy 479 



Upper cheek-teeth 480 



Lower cheek-teeth 486 



Incisors and canines 486 



Milk dentition : 490 



Skull 494 



Limbs 500 



Merychippus intermontanus Merriam 505 



Merychippus calamarius stylodontus, n. var 505 



Merychippus sumani Merriam 505 



Protohippus? or Pliohippus?, sp 505 



Suidae 507 



Oreodontidae 507 



Merycochoerus? buwaldi, n. sp 507 



Camelidae 512 



Bovidae 517 



Merycodus necatus? Leidy 517 



Merycodus? coronatus Merriam 521 



Cervidae. 524 



Dromomeryx or Cervus?, sp 524 



Ricardo fauna 525 



Relation of the Ricardo fauna to its environment 525 



Stage of evolution and relationships of the Ricardo fauna 526 



Relation to Tertiary faunas of the Great Basin province 526 



Comparison with faunas of the Pacific Coast province 530 



Comparison of the Ricardo fauna with that of the American Tertiary 



outside the Great Basin and Pacific Coast provinces 531 



Description of fauna 533 



Testudinate remains 533 



Carnivora 533 



Canid, small, near Canis? vafer Leidy 533 



Aelurodon? aphobus, n. sp 535 



Aelurodon?, possibly aphobus, n. sp 537 



Aelurodon?, n. sp. A 538 



Aelurodon? n. sp. B 539 



Aelurodon or Tephrocyon, sp. C 539 



Aelurodon or Tephrocyon, sp. D 540 



Limb elements 541 



Mustek? buwaldi, n. sp 542 



Ischyrosmilus Merriam 543 



Ischyrosmilus osborni, n. sp 545 



Felid limb elements 546 



Felid?, indet 546 



Rodentia 547 



Proboscidea 548 



Ife Tetrabelodon?, sp 548 



Equidae 548 



Hipparion mohavense Merriam 549 



Hipparion mohavense callodonte Merriam 553 



