PHYSICAL COXDITIOXS AND AGE INDICATED BY FLORA OF ALUM BLUFF FORMATIOX. 



47 



oontrul Mississijipi und is jii pLu'cs !il)mi(liUit 

 but ovcrvwhoro fragmentiirv. In the absi'uci' 

 of fairly well jireservecl specimens showing the 

 rachis and acumen it is impossible to distin- 

 guish this form froni the AVilcox species Saha- 

 lites graq/anus BeiTv or the Oligocene species 

 SdhdlJlift virlshnrgeiifiiN Berry, so that possibly 

 the latterspecies, represented byincomplete ma- 

 terial, may be present in the Alum Bluff sands, 

 although I consider this extremely doubtfid. 



SabaUtes graijanus differs from the present 

 species in the expanded upjier end of the rachis, 

 the longer and more gi-adually naiTOwed acu- 

 men, and the more numerous rays, which are 

 usualh- more conspicuously veined. 



Tlie fragments of rays which are so common 

 in some of the deposits of the Vicksburg groujj 

 and MhicJr are made the basis of Sahalites inclcs- 

 hiirgensis are to be distinguished from 5. apa- 

 lachicolensis chiefly l)y their much more promi- 

 nent venation and longer and more slender 

 acumen. The present species at its region of 

 maxinuim occurrence at Alum Bluff is badly 

 jj^infested with a leaf-spot fungus which I have 

 described as Pestalozzifes sahalana Berry, n. sp. 

 The foliage of jialms is abundant and well 

 distributed throughout the deposits of the 

 Wilcox, Claiborne, Vicksburg, and Apalachi- 

 cola groups, indicating the abundance of plants 

 of this type in southeastern North America 

 during the Tertiary period. Few of these 

 remains represent entire leaves, and in many 

 places only fragments of rays are preserved. 

 Palm leaves are notoriously difficidt of deter- 

 mination, and the bidk of remains represent- 

 ing flabellate fan palms with an acumen are 

 referred by American students to the genus 

 Sa])alites and by European students to Sabal. 

 Two methods of specific differentiation are 

 possible. Minor differences and stratigraphic 

 position may l)e ignored, as in the case of the 

 geographically and geologically wide-ranging 

 Sahal major Unger of Eurasia, or minor differ- 

 ences that also represent differences in geologic 

 age may have considerable weight in specific 

 differentiation. The latter is the method that 

 I have found most useful from both the bio- 

 logic and the geologic viewpoint. 



The extreme tropical climate of Vicksburg 

 and Catahoida time, which is reflected in the 

 abundant traces of palms found in deposits of 

 Vicksburg or Catahoida age from Texas east- 

 ward, continued througli the time of deposition 

 30841°— 16 2 



of tlie Chipola marl member of the .Uum Bluff 

 formation. Fortunately conditions were fav- 

 oralile for petrification, and fragments of petri- 

 fied ])alm tnmks, many of them of large size, 

 are abundant throughout the area underlain 

 by the Vicksburg or Catahoula deposits. 

 Severn species of Palmoxylon have been de- 

 scribed from these deposits. So far as I am 

 aware no petrified palms have thus far been 

 (>l)tained from the Alum Bluff sands, })ut palm 

 foliage is very abundant in the leaf-l)earing 

 lens at Alum Bhiff. I have never seen so great 

 an abundance of stipes and rays of palms as 

 occur at this outcrop. In places whole laj-ers 

 consist of a mass of frayed and tangled rays in 

 a matrix of sandy alluvium. They are usuaUy 

 much macerated, and onl}- here and there can 

 larger fragments of leaves be found. They are 

 almost equally a])imdant in the similar mate- 

 rials croppmg out near Ilagian, Miss. This 

 suggests the presence near the coast in late 

 Alum Bluff time of extensive palmetto swamps 

 or brakes along the lower reaches of a sluggish 

 river or estuary ovUj a few feet above mean 

 water level — not flooded or true swamps, but 

 subject to periodic overflow. 



Occurrence: Hattiesburg clay, Raglan, For- 

 rest County, Miss, (common; collected by E. 

 W. Berry) ; and near Chicoria, on Chickasaw- 

 hay River, Wayne County, Miss, (collected by 

 E. AY. Berry). Alimi Bluff formation, .Uuni 

 Bluff, Liberty County, Fla. (collected by E. W. 

 Berry), and Boynton Bluff, Choctawhatchee 

 River, Fla. (collected by E. H. Sellards). 



Collections: United States Xationtjl Museum. 



Subclass BICOTYLEDON.S:. 



Order FAGALES. 



FamUy XJLMACE^. 



Genus ULMUS Linne. 



Ulmus floridana Berry, n. sp. 



Plale IX, figm-es .5-7. 



Leaves of medimu or small size, ovate-lan- 

 ceolate in general outline, -tt-ith slightly ine- 

 quilateral cuneate rounde<l or sul)cordate 

 base, and a gradually narrowetl, somewhat ex- 

 tended acuminate tip. Length from 4 to 7 

 centmieters. Maximum width, in the basal 

 half of the leaf, from 1..5 to 3 centimeters. 

 ^fargins entire at the extreme base, above 

 whi< h they are finely and sharjdy doi'bly ser- 



