18 Mamm, 
MAMMALIA. 
single deciduous molai’ of Marsupials is the third, not the fourth, pre- 
molar, the latter tooth being therefore permanent in the Marsupials, 
between which and the Carnivora the Creodonta are intermediate, having 
both third and fourth milk premolars replaced by permanent teeth. The 
following identifications are made, pp. 1018 & 1019: — Fachycena = 
Mesonyx ; Apterodon^ Fischer, = Mesonyx. There are 4 good species of 
Mesonyx. 
Miacid;e. 
^ Miacis canavus, p. 189, and M. hrevirostris, p. 190, spp. nn. (foss.), 
, E. D. Cope, Bull. U. S. Geol. Surv. vi., Wind River Beds. 
Didymictis massetericus^ p. 159, and curtidens^ p. 160, spp. nn. (foss.), 
; E. D. Cope, P. Am. Phil. Soc. xx. D. leptomylus^ sp. n. (foss.), id. Am. 
I Nat. xiv. p. 908. D. altidens, sp. n. (foss.), id. op. cit. xv. p. 746. All 
' are from the Wasatch beds of Wyoming. 
D. 'dawkiniunus, sp. n. (foss.), id. Bull. U. S. Geol. Surv. vi. p. 191, 
Wind River Beds. 
LEPTICTJDiE. 
/ Ictops dideljdioides, sp. n. (foss.), E. D. Cope, Bull. U. S. Geol. Surv. 
vi. p. 192, Wind River Beds. 
Lipodectes xienetrans and pelvidens, g. & spp. nn. (foss.), id. Am. Nat. 
XV. p. 1019, Lowest Eocene of New Mexico. 
Triisodon quivirensis, g. & sp. nn. (foss.), id. 1. c. p. 667, and P. Am. Phil. 
Soc. xix., p. 485, Puerco beds. Lower Eocene of Now Mexico. T. heil- 
prinianus^ sp. n. (foss.), id, P. Am. Phil. Soc. xx., p. 193, Lowest Eocene 
of New Mexico. 
Deltatherium fundaminis, g. & sp. nn. (foss.), zW. Am. Nat. xv. p. 337, 
and P. Am. Phil. Soc. xix. p. 486, Puerco beds. Lower Eocene of New 
Mexico. D. absarokce, sp. n. (foss.), id. Am. Nat. xv. p. 669, “ Wasatch 
Eocene.” 
Styxiolophus bicuspis, id. Am. Nat. xiv. p. 746, and S. whitite,id. P. Am. 
Phil. Soc. XX. p. 161, spp. nn. (foss.). Lowest Eocene of Wyoming. The 
former species is referred to the genus Ictops ; id. Bull. U. S. Geol. Surv. 
vi. p. 192. 
OxY.®NIDiE. 
/ Protop>salis tigrinus^ g. & sp. nn. (foss.), E. D. Cope, Am. Nat. xiv. 
/ p. 745, and Bull. U. S. Geol. Surv. vi. p. 193, Wasatch beds of 
\Wyoming. 
V 
MESONYCHIDiE. 
Apterodon gaudryi, g. & spp. nn. (foss.),P. Fischer, Bull. Soc. G^ol. (3) 
viii. pp. 288-290. Phosphorites du Quercy.” Allied to Hycenodon and 
Pterodon. (According to Cope, supra, this = Mesonyx.'] 
