RHAMNALES. 



277 



Spcondiirics thin, about, nino snliopposito to 

 iilternato pairs, divcrsjjino; from the iniilrih at 

 angles of iiKirc than -15°, and hcconiinij; nnu-li 

 more open toward the tip <if tlic h'af, iri'ci:;u- 

 hii'ly spaccnh rcgnlarly cnrvcd, caniptoch'otnc in 

 the marginsJ region. Tertiarics niostlyobsoh't(>. 

 Leaf substance tluck. Texture coriaceous. 



This species may be compared with the sani<' 

 western species as Sapindiifi formosus Berry. 

 It is much lil^e Saplndus formosus in size and 

 genercJ appearance but is readily distinguished 

 by its broader form, shorter tip, nuire coria- 

 ceous texture, less ascending seconthiries, 

 broader, more inequilateral base, antl shorter 

 petiole. It is common at Purvear, Tenn., 

 and greatly resembles the forms from the 

 Raton formation wiiich are referred by Knowl- 

 ton to Sapindus affinis Newberry. 



Occurrence. — Lagrange formation (in beds of 

 Wilcox age), Purvear, Henry County, Tenn., 

 common (collected by E. W. Berry), and Wick- 

 liffe, Ballard County, Ky., common (collected 

 by L. C. Glenn). 



Collections. — U. S. National Museum. 



Order RHAMNALES. 

 FamUy BHAMNACEffi. 

 Genus ZIZYPHUS Linne. 



ZizYPHUs FALCATUS Bcrrv, n. sp. 



Plates LXIX, figure 5, an<l I. XX, figures 1 and 2. 



Description. — Leaves of viu-ia])le size, lance- 

 olate or ovate-lanceolate in outline, invaria- 

 bly falcate, the base decurrent and the tip 

 gradually narrowed, acuminate. Length ranges 

 from 7 to 13 centimeters. Maximum width, 

 which is in the lower half of the leaf, ranges 

 from L25 to .3 centimeters. Margins irregu- 

 larly and as a rule prominently crenate, 

 the teeth becoming obsolete at the extreme 

 base and in the tip; less close set and promi- 

 nent in the smaller, narrower leaves. Texture 

 coriaceous. Petiole short, stout, and curved, 

 7 to 12 millimeters in length. Midrib stout, 

 prominent, curved, becoming thin in the tip. 

 Lateral primaries one on each side, suljoppo- 

 sitc, suprabasilar, relatively stout but much 

 less so than the midrib; they diverge at acute 

 angles, the acuteness depenchng on the relative 

 width of the leaf, and pursue courses pandlel 



with the respective laterd margins, joining 

 secondaries above tlie middle (if the l<>af. The 

 secdndaries consist of tlu-ee categories; an 

 i>))]iosit(> pair diverge from the base of the 

 midril) and ])ursne a course parallel witli the 

 lateral primaries and margins for a varviu'^ 

 (Hstance upward; two or tin-ee thin camptn- 

 drome pairs arise from the midrib in tlie tip of 

 the leaf: and thin ciiniptodromc secondaries 

 run outward from the lateral i)rimaries. Tlie 

 ])rimaries and mich-ib are connected by mimer- 

 ous thin, nearly straiglit, transverse veinlets, 

 largely immersed in the thick leaf sulistance. 



This species is in many respects rather close 

 to Zizyplms meigsii (Lesquereux) and may 

 possibly represent variants of that species, 

 whose leaves are notoriously variable. There 

 are abundant grounds, however, for specific 

 difTerentiation. Zizj/jdim meigsii appears to 

 be invariably much widened below, so that 

 without the acumen its outline' would ho orbic- 

 ular, and some individuals liave a cordate ])ase. 

 It develops a very long attenuated acumen, 

 and as a rule h.os large close-set teeth. Zizy- 

 plms falcatns, on the other hand, is smaller, lan- 

 ceolate-falcate in form, and no specimens are 

 much widened proximad. Tiie base is cuneate 

 and decurrent, and the tip regularly tapering. 



The leaf substance is more coriaceous. The 

 teeth are smaller and more distant in the 

 smaller leaves. 



Ztzyphus falcatus is nearer to the existing 

 American species of Zizyphus than is the asso- 

 ciated Zizyplms meigsii and is a tyjiical mem- 

 ber of the genus. Among previously described 

 fossil forms it greatly resembles Zizyphus 

 ungeri Heer,' a species that is exceedingly com- 

 mon in the European Oligocene. Ettingshau- 

 sen in his account of the flora from Haering in 

 the Tyrol has figured a large number of speci- 

 mens of this species which admirably illustrate 

 its variations. 



Zizy plms falcatus is represented in the subse- 

 ffuent Clail)orne deposits of the embayment 

 region by the similar Zizyphus claibornensis 

 Berry. 



Occurrence. — Lagrange formation (in l)e(ls of 

 Wilcox age), Puryear, Ilem-y County, Tenn. 

 (collected by E. W. Berry). 



Collection. — U. S. National Museum. 



1 Ileer, Oswald, Flora tertiaria Helvetiae, vol. 3, p. 74, pi. 122, fig. 25,. 



1859. 



