PHYSICAL CONDITIONS INDICATED BY THE FLORA OF THE CALVERT FORMATION. 



69 



from Vir<;ini:i southward to I'lorida, Cuba, and 

 tro])ic!d America. 



The fossil s[)eeies are numerous and range 

 from tlie I'pper Cretaceous to the present. 

 ^imong ])reviously described fossil forms Cassia 

 ioj-aforniis is identical with some of the heaves 

 from th(. Tortonian of Ooningen, Baden, which 

 Heer ' refei-s to Cassia llgnUum Unger. It i.s 

 also very similar to CxsaJpin'ta esdicri Heer,- 

 from Ooningen. 



Occurrence: Good Hope Ilill, I). C. 



Order SAPINDALES. 



Family ILICACEjE. 



Genus ILEX T.inne. 



Lex calvertensis Berry, n. sp. 



Plate XII, figure 8. 



Leaves small, ovate in general outline, with 

 a bluntly pointed apex and base, the latter 

 slightly inequilateral. Length about 16. .5 mil- 

 limeters; maximum width, midway between 

 the ape.x and base, about 7 millimeters. Mar- 

 gins entire for most of their length, apically 

 with slight and remote denticulations. Texture 

 subcoriaceous. Petiole short and stout, 

 about 1.7.5 millimeters in length. Midrib stout 

 and prominent proxiniad, attenuated distad, 

 curved. Secondaries thin; five subopposite 

 pairs diverge from the midrib ^^t wide angles 

 and are conspicuously camptodromo in the 

 marginal region. Tertiarj' venation obsolete. 



Ilex is a large genus with over 100 described 

 fossil species and over 200 existing species. It 

 ranges from the Upper Cretaceous to the pres- 

 ent, and existing forms are found in all tropical 

 and temperate regions except western North 

 America, Australia, New Zealand, and New 

 Guinea. The largest number occur in Brazil 

 and Guiana. 



Hex calvertensis may be compared with the 

 existing Hex romltoria Aiton, a small tree of the 

 coastal region of the South Atlantic and Gulf 

 States. It also resembles Flex I'omitoriafolia 

 Berry, a coastal form of the lower Eocene 

 (Wilcox group) of the Mississippi embayment, 

 with which it may be affiliated. 



Occurrence : Good Hope Hill, D. C. 



■ ITeer, Oswald, Flora tertiaria Uelvetiae, vol. 3, p. 121, pi. I.'i8, figs. 

 23-28, 1839. 

 s Idem, p. Ul, pi. 155, fig. 21. 



Order KHAMNALES. 



Family KHAMNACEa:. 



Genus BERCHEMIA Necker. 



Berchcmia priscaformis Berry, n. sp. 



Plato XII. fi-ures 11, 12. 



Leaves small, lanceolate, with equally acumi- 

 nate apex and base. Length about KJ milli- 

 meters; maximum widfli l)etween apvx and the 

 base, a])out 5.5 millimeters. Margins entire, 

 sligiitly uiuhilate corresponding with the camp- 

 todrome eiulings of the secondaries. Texture 

 subcoriaceous. Petiole relatively long and 

 slender, about 2 millimeters in length. Midrib 

 relatively stout, somewhat curved, prominent 

 on the lower surface of the leaf. .Secomhiries 

 thin but prominent, numerous; seven or eight 

 pairs diverge from midrib at regular intervals 

 and acute angles, curving slightly and sul)- 

 parallcl, camptodrorae close to the margins. 

 Tertiarios mostly obsolete, a few percurrent 

 ones seen. 



This characteristic little species is scarcely 

 distinguishable from the smaller and more 

 lanceolate leaves of Bcrchemia scandens (Hill) 

 Trelease, a high-climbing shrub frequcntuig 

 low woods from Virginia to Florida and from 

 Missouri to Texas. The genus contains about 

 10 existuig species, the others being natives of 

 Asia and tropical Africa. About half a dozen 

 fossil species have been described. These 

 include a rare form in the Aquitanian of France, 

 another in the Burdigalian of Boliemia. species 

 in the Pliocene of France anil llollaml, and tlie 

 w'lAeiipvQ&A Bercliemiamultinenis (Alex. Braun) 

 Heer. B. multinems has a recorded range 

 from the Tongrian to the Astian throughout 

 central and southern Europe. It has been iden- 

 tified in the lower Eocene (Raton, Denver, and 

 Fort Union formations) of the Rocky Moun- 

 tain province and in the Miocene of Oregon. 



Tlie American material referred to B. multi- 

 nervis is larger and wider than the Calvert 

 species and lias a more pronounced tertiary 

 venation. Some of the smaller leaves of B. 

 multinerms from European localiti(>s are much 

 like B. pnscaformis, as for example a leaf fig- 

 ured by Heer ^ from the Tortonian of Oeningen, 

 Baden, which is but slightly larger or wider. 



> Idem, pi. 123, fig. 17. 



