270 



I.OWEK EOCKXE FLORAS OF SOUTHEASTERX XORTH AMERICA. 



single (ir (l(nil)lv si>rr;ito teeth, wliicli increase in 

 si/.c gradually I'nnii below upward xuitil they 

 are large and prouiiuent and directed upward. 

 Midrih stout, curved, prominent on the lower 

 surface of the leaflet. Secondaries rather stout, 

 prominent, numerous, subparallel; about 2-5 

 subopposite to alternate pairs diverge from the 

 midrib at angles of about 60° to 6.5°, curving 

 slightly, each ending craspedodromely in a 

 ]uajor marginal tooth; they incresise in caliber 

 and interval of spacing from below upward, and 

 one or two pairs at tlie extreme base are camp- 

 todrome. Near the tips each sends a branch 

 from its lower outer side to a minor marginal 

 tooth, where the teeth are developed. Ter- 

 tiaries fine, at approximately right angles to 

 the secondaries, usually straiglit subparallel 

 and percurrent, largely obsolete by inmiersion. 

 Texture subcoriaceous. 



This species is based primarily on a specimen 

 (U. S. National Museum, No. 2521) collected at 

 Wicklifle, Ky., many years ago by R- H. 

 Loughridge, for whom it is named. It was 

 identified by Lesquereux with Myrica copeana, 

 which he had described from Florissant, Colo., 

 in 1874 and 1878. 



The plant beds at Florissant are much 

 younger than the Wilcox and are now usually 

 r(>garded as middle or iipper Miocene. The 

 flora which they contain indicates an upland 

 mountain-lake basin. Though the superficial 

 resemblance between Myrica copeana Lescpie- 

 reux and Cupania loughridgii Berry is close and 

 each is represented by scanty niaterial, there 

 are certain well-marked difl'erences. Cupania 

 loughridgii is more elongated and inequilateral, 

 has a rounded sessile base, less prominent non- 

 af|uiline teeth, less curved secondaries, right- 

 angled percurrent instead of ol^liipie tertiaries, 

 and a wider angle of divergence of tlic marginal 

 branches of the secondaries. 



The character of the entire, rounded, incejui- 

 lateral, and sessile biise clearly indicates that it 

 represents a leaflet of a compound leaf, and its 

 size suggests that the leaf was once-pimuite, 

 like those of most of the Sapindacea? and Jug- 

 landacciB. This at onc(> removes from ct)nsid- 

 eration such genera as Myrica, Quercus, Dryo- 

 phyllum, and most of the Proteaceae, which offer 

 superficial resemblances. The craspedodrome 

 secondaries prohibit comparisons witli the dif- 

 ferent genera of the Juglandaceae or with Frax- 

 inus. There is some resemblance to the prote- 



uceous genus Rhopala and to members of the 

 tropical family Burseraceie. The Sapindacea? 

 seem to ofl'er the surest comparisons, and in this 

 family the genera Cupania, Dilodendron, and 

 Tiu)uina deserve especial mention. All are 

 strictly American in tlie existing flora. Cupania 

 contains :]0 to .35 species in the Tropics and sub- 

 tr(>])ics, Dilodendron 1 species in Brazil, and 

 Thouina 14 or 15 species in tlie West Indies 

 and Mexico. 



Occurrence. — Lagrange formation (in beds of 

 Wilcox age), Wickliffe, Ballard County, Ky. 

 (collected by R. H. Loughridge and L. C. 

 Cdenn). 



Collection. — U. S. Xational Museuni. 



Genus DODON'.^.4 Linne. 



DoDox.EA wiLcoxiAXA Bcrrv, n. sp. 

 Plate XXXVIII, figure 2. 



Description. — Leaves small, lanceolate or 

 oblanceolafc in general outline, the apex nar- 

 rowly rounded or shortly pointed and the base 

 narrowly cuneate. Length about .3 centime- 

 ters. Maximum width, at or above the mid- 

 dle, about 0.75 centimeter. Margins entire, 

 somewhat revolute. Texture coriaceous. Pe- 

 tiole short anil stout, not enlarged, shghtly 

 curved, about 3 milUmeters in length. Midrib 

 stout and prominent. Secondaries relatively 

 prominent, about ten, mostly opposite pairs. 

 They diverge from the midrib at wide angles, 

 as large as 80° in the upper part of the leaf, 

 and are either straight or curved, becomuig 

 thin and camptodrome close to the nuirgins. 

 Tertiaries line, Vjut distinct in the fine-grained 

 clay matrix. They are largely percurrent, and 

 have cross nervilles that form quadrangular or 

 pentagonal meshes. 



This well-marked species seems clearly refer- 

 al)le to Dodoniea, especially in view of the 

 ciuu'acteristic fruits of Dndonsea Icnowltoni, 

 which occur at Puryear. It is closely similar 

 to the less markedly oblanceolate leaves of the 

 modern Dodoniea nscosa Liime as well as to 

 other West Inchan species of Dodonaea — for 

 exampl(% Dodonxa angnMifolia Swartz. It is 

 not unlike a form from the Tertiary of Bolivia 

 described by Engelhardt ' as Gaylussada ter- 

 tiaria and comparetl with the existing Bra- 

 zilian species Gaylussacia ledifolia Martius. 



' Engelhardt, Hermann, Naturvviss. GeseU. Isis in Dresden Abh., 

 1S94, p. 0, pi. 1, ngs. 8, 9. 



