268 



LOWER EOCEXE FLOEAS OF SOUTHEASTEF.X XOBTH AMERICA. 



From this region the lateral margins as they 

 continue toward the base are full and broadly 

 rounded. Distad the margins are fiill for a 

 considerable distance, becoming incurved as 

 the apex narrows and curving upward to form 

 the extended, narrowly acuminate tip. Mar- 

 gin regularly and finely dentate, the denticula- 

 tions approaching the serrate form in some 

 specimens, becoming less pronovmced and 

 finally obsolete at the extreme base of the leaf. 

 Texture firm but leaf substance not thick. 

 Petiole relatively long and stout, about -3 centi- 

 meters in length in a specimen below the aver- 

 age size. Midrib stout below, becoming thin 

 distad. Secondaries stout proximad, numer- 

 ous, 10 to 1.5 paii^, regularly spaced and ap- 

 proximately parallel, subopposite to alternate, 

 becoming farther apart in the apex of the 

 leaf; all camptodrome. They branch from the 

 midrib at a wide angle, which ranges from .5-5' 

 to 90°, they curve but slightly imtU they ap- 

 proach the margin, where they sweep upward 

 more or less parallel with the margin in a suc- 

 cession of arches of abruptly diminishing cali- 

 ber. Tertiary system of thin intermediate 

 veins parallel with some of the secondari^ 

 and haKway between them and transverse, 

 mostly perctxrrent veinlets. 



This very handsome species is well marked 

 and perfectly distinct from previously de- 

 sc-ribed forms, although it resembles somewhat 

 HicKn^.a antiqu<frum Csewberry) Knowlton. 

 Its extreme variability in size is well shown in 

 Plate LXII, aside from which its features are 

 relatively constant. The smaller leaves like 

 the one shown in figure 1 are more ovate-lanceo- 

 late and symmetric and less extended apically, 

 but the larger are less symmetric, rounded and 

 somewhat inequilateral below, and greatly 

 extended apically, with corr^ponding changes 

 in the angle of divergence of the secondaries. 

 The species Is extremely abundant in aU sizes 

 at the locality south of Grand Junction. Tenn., 

 both the smallest and the largest figured speci- 

 mens having come from this outcTop. It is 

 about equally common and variable in size at 

 theLamar locality but Is less common elsewhere. 

 It is also found in the Raton formation of the 

 southern Rocky Mountain province. A large 

 number of fragments from Bastrop County, 

 Tex., are douhitfuUy referred to this species. 

 They have identical margins and venation, 

 except that the secondaries are more ascending. 



Their much broken condition prevents their 

 positive determination. 



A ntmaber of previously described Tertiary 

 species are close enough to Euonyrrois splen- 

 deng to come within the limits of this discus- 

 sion. Among these Euonymus proserpime 

 Ettin^hausen ' is perhaps most like this Wil- 

 cox species. It comes from the Aquitanian 

 of Priesen, Bohemia, and is characterized by 

 its more prominent serrate teeth, fewer sec- 

 ondaries, and less extended tip. Ettingshausen 

 compared it with the modem species Euonymus 

 acundnatus, E. vaUichn, E. javanicus, E. pen- 

 dulum, E. hamiltonianus, and E. atropurpureus, 

 and considered it most like the first, a Mexican 

 species. 



A nimiber of other species of Euonymus 

 have been described from the European Aqui- 

 tanian stage, but they are much smaller leaves, 

 though in other respects much like the fore- 

 going. 



American Tertiary species are less numerous 

 than the European. A well-marked early Eo- 

 cene form (Fort Union) from Montana was 

 named Euonymus xantTioVtJifnsxs by Ward - and 

 compared with the living American Euonymus 

 atropurpureus Jacquin, and the East Indian 

 Euonymus pendulus WaUich. It has coarser 

 teeth and lacks the apical elongation of Euo- 

 nymus spUndens, but except for its smaller 

 size is rather similar to that species. Another 

 similar American species is Euonymus jltxifo- 

 lius Lesqueretix,' which comes from the Green 

 River Eocene of Wyoming. It is about the 

 size of the average specimens of Euonymus 

 SpUndens and is very similar in general outline 

 and distal elongation but is relatively some- 

 what narrower, has fewer secondaries, and the 

 teeth are very prominent, upwardly prolonged, 

 and serrate. 



About twenty fossil species of EuonjTnus 

 have been described, ranging in age from the 

 ba.se of the Eocene to the Pleistocene. The 

 existing species number about 65 and are widely 

 distributed throughout the northern hemis- 

 phere becoming massed in the southeastern 

 Asiatic region, with many species in the up- 

 lands of India and China and throughout Ma- 

 laysia. There are five indigenous specic-s in 



1 f.nhigshausai, C, von, Die fossflc Flora des Tertiar-Beckens von 

 Bflin, Theil 3, p. .30, pi. 41', Bgs. f,, 7, 1*69. 



'Ward, L. F., U. S. Geol. Survey Bull. 37, p. 82, pi. 37, figs. 1, 2, 1887. 



' Lesquereox, Leo, The Cretaceous and Tertiarr floras, p. 1^, pi, 38, 

 8«. 13, l<s«. 



