NO. I LOWER EOCENE MAMMALIAN FAUNAS — GAZIN 33 



weaker posterointernal crest and weaker and much lower position of 

 the metaconid of P4, as discussed in 1958 (p. 27), seemed to warrant 

 separate recognition. 



A lower jaw (U. of C. No. 46705) from the Dad locality, recently- 

 sent to me by McKenna, surely represents this species. It was found 

 about 6.9 miles north of Baggs in a yellow weathering claystone 

 approximately 100 feet below the Tipton tongue. P4 in this specimen 

 is so completely like that in the type of Chlororhysis knightensis that 

 I have no hesitancy in referring it to this form. It seems, moreover, 

 to demonstrate the characters of the lower molars not previously 

 known. 



Ml in the Dad specimen (pi, 12, fig. 10) is a little smaller than 

 in Loveina zephyri and the posterior wall of the trigonid where it 

 is joined by the crista obliqua is simpler and more nearly flat. In 

 Loveina the posterior wall of the trigonid is offset and the crista 

 obliqua joins it in the deepest part of the indentation. Also, the 

 posterior wall lingual to the crista obliqua is more rugose or plicate. 

 The talonid basin of Mi in Chlororhysis is shallower and the sur- 

 rounding crest is smoother with less emphasis on the separate cusps. 

 In Loveina the hypoconulid of Mj is separated from the nearby 

 hypoconid by a notch which is essentially missing in Chlororhysis. 

 Moreover, the pair of crests from both the protoconid and hypo- 

 conid in Loveina seem to form a sharper V. In Chlororhysis these 

 form a more blunt angle or a better U shape. 



The trigonid is damaged in M2 of the Dad specimen but the talonid 

 exhibits essentially the same broad but shallow basin and compara- 

 tively even surrounding crest as in Mi. M3 is about the length of M2 

 but noticeably narrower with a rapidly tapering talonid. The trigonid 

 portion of Mg is relatively short anteroposteriorly but exhibits a 

 small paraconid in a nearly lingual position. 



A second specimen from La Barge, a jaw fragment with only Mi 

 (U.S.N.M. No. 22385), had been cataloged as Loveina zephyri but 

 it shows a much closer correspondence to the Mi in the Dad speci- 

 men of Chlororhysis knightensis. It seems advisable at this point, 

 in view of the rarity of Loveina zephyri specimens, to note that the 

 Lost Cabin lower jaw, U.S.N.M. No. 18439, described by White 

 (1952, p. 193) as belonging to L. zephyri, is undoubtedly of Absaro- 

 kius noctivagus, so that the information there furnished regarding 

 posterior molars does not apply to Simpson's species. 



It is of further interest to note that although Chlororhysis is near 

 Loveina, which seems rather typically omomyid, the differences 



