170 



SHORTER CONTRIBUTIONS TO GENERAlr GEOLOGY, 1921. 



lected in the Dakota sandstone of southern 

 Kansas and subsequently recorded by Bartsch 

 from the same formation in Iowa, is repre- 

 sented in the lower beds of the Tuscaloosa 

 formation of western Alabama and in the 

 Woodbine sand at Ai'thurs Blirff, Tex., by 

 leaves which are identical in all their characters 

 with the type material and which seem to be 

 closely allied to the Tertiary and modern forms 

 of Rhamnus. It has been reported by Engel- 

 hardt from the Cenomanian of Niederschoena, 

 Saxony, but this record may well be considered 

 doubtful. 



Genus ZIZYPHUS Adanson. 



Zizyphus lamarensis Berry. 



Plate XXXVI, figure 4. 



Ziziiphus lamarensis Berry, Torrey Bot. ("hil) Bull., vol. 

 39, p. 398, pi. 31, fig. 1, 1912; U. S. ("leol. Survey 

 Prof. Paper 112, p. 112, 1919. 



Leaves elliptical, 4.5 to 5 centimeters in 

 length by 3 centimeters in maximum width, 

 about midway between the apex and the base, 

 though slightly nearer the base; base full and 

 rounded ; lateral margins full and rounded ; apex 

 romided, slightly- less full than the base; mar- 

 gin with regular but shallow crenate teeth, 

 becoming less prominent toward the base. 

 Midrib slender but prominent, straight. Lat- 

 eral prhnaries one on each side, diverging 

 from the midrib at its extreme base at an acute 

 angle (about 10°), thin, slightly curved mward 

 above the middle, joining a secondary in the 

 apical part of the leaf. Secondaries from 

 the midrib two or tlu'ce alternate thin pairs 

 in the apical region, camptodrome; seconda- 

 ries from the lateral primaries five or six in 

 number, on the outside, curved, camptodrome; 

 the lowest secondary is longest and branches 

 at the most acute angle (about 10°) and from 

 the extreme base; each successively higher 

 secondary subtending a slightly larger angle 

 and following a somewhat shorter course. 

 Internal tertiaries more or less percurrent, 

 marginal ones similar to the secondaries from 

 the prin^ari(^s in their arrangement and course, 

 thin and camptodrome. 



This handsome species of an undoubted 

 Zizyphm was described recently from very 

 scanty material obtained in the Woodbine 

 sand of Texas. It is entirely distinct from 

 any previously described Cretaceous species 

 and is much closer to some of the Tertiary 

 and still existing forms. 



Zizyphus has not yet been discovered in the 

 European Cretaceous, but it is represented in 

 the Western Hemisphere by fom" or five well- 

 marked types. The nearest to the present 

 species is Z. (iroenlandiciis Heer,'" which oc- 

 curs in the Magothy formation on Marthas 

 Vineyard and in the Patoot beds of western 

 Greenland. It is of about the same size but 

 relatively wider than the Texas form and has a 

 somewhat different venation and much coarser 

 teeth. The species from the Magothy of New 

 Jersey, Z. cUffiroodensis Berry,'" is a larger, 

 lanceolate, entire-margined form. The two 

 species from the Cretaceous of Long Island, Z. 

 eJegans ^' and Z. oblongus,'-'^ described by Hol- 

 lick, are much smaller, entire-margined forms, 

 and HoUick's Z. leivismna,^^ another Creta- 

 ceous species from the same locahty, is a small 

 lanceolate leaf of doubtful affinity. 



The existing species of Zizyplims number 

 aliout 40 and are largely indigenous in the Indo- 

 Malayan region, although the genus is repre- 

 sented in subtropical or tropical America, 

 Africa, and Australia. One modern species, 

 Zizyphus vulgaris Lamarck, an oriental form, 

 has foliage almost identical with Z. lamarensis, 

 the outhne, margin, and veiiation bemg the 



same. 



Family VITACEAE. 



Genus CISSITES Heer. 



Cissites formosus Heer. 



Plate XL. figure 5. 



Cisi'Uen foniiosii.i Heer, Flora fossili.-f arctica, vol. fi, pt. 2, 



p. 85, pi. 21, figs. 5-8, 1SS2. 

 Le.squereux, The flora of lln' Iiakota group, p. 101, 



pi. 21, fig. 5, 1892. 

 ?Hollick, Torrey Bot. Clul. I'.ull., vol. 21, p. 57, pi. 



174, fig. (), 1894; The (Vetaceous flora of southern 



New York and New England, p, 94, pi. 37, fig, 7, 



1906. 

 Nfwberry, The flora of the Amboy clays, p. 107, 



pi. 47, figs. 1-8, 1896. 

 Herry, New Jersey Geol. Survey Bull. 3, p. 185, 1911; 



U. S. Geol. Survey Prof. Paper 112, p. 115, 1919. 



Heer's description, published in 1882, is as 

 follows: 



('. fciliis palmatis, profunde trilobatis, lobo medio basi 

 contracto, trilobato, lobis obtusis. 



2' Heer, Oswald, Flora fossilis arctica, vol.7, p. 42, pi. 62, fig. 20. 1883. 



"' Berry, E. W., Johns Hopkins Univ.Circ, new ser., No. 7. p. S.S, flg.5, 

 1907. 



31 HoUick, Artlmr, Torrey Bot. Club. Bull., vol.21, pi. t7fi, fl^.S. 1.S94. 



s= HoUick, Arthur, The Cretaceous flora of southern New York and 

 New England: U. S. Geol. Survey Mon. 50, p. 92, pi. 34, figs. 9, ill, 1907. 



M HoUick, .\rthur, Torrey Bot. Club Bull., vol. 21, p. 5S, pi. 180, 

 flg. 13, 1S94. 



