162 



LOWER EOCEXE FLORAS OF SOUTHEASTERN XOETH AMERICA. 



SYSTEMATIC DESCRIPTIONS. 



Phylum THALLOPHYTA. 

 Class FTXNGI. 

 Order PYKENOMYCETES ?K 

 Genus C.-ENOMYCES Berrj, n. gen.' 



The presence of spots of different shapes on 

 the leaves of fossil plants is exceedmgly 

 common, and a very large number of so-called 

 species of fossil leaf-spot fmigi have been de- 

 scribed by Ettingshausen. Heer, Saporta, and 

 others. These species are referred for the most 

 part to the genera Sphieria. Phacidium, Do- 

 thidia, Depazea. Sclerotia, Hysteria. Rhytisma, 

 Xylomites. and the hko. A large list of such 

 forms was published by MeschineUi in 1892.- 

 All these determinations are based entirely on 

 superficial similarities between the fossil and 

 some modem leaf-spot fungus, of which there 

 are thousands of species, most of them dis- 

 tinguishable only by their methods of repro- 

 duction or the morphology of their reproduc- 

 tive parts. 



The identification of these fossil forms obvi- 

 ously rests on a very insecure foundation, es- 

 pecially when it is recalled that scale insects 

 and a great variety of msect galls would re- 

 semble epiphyllous fungi when preserved on 

 impressions of fossil leaves. Nevertheless large 

 numbers of midoubted fungi are preserved in 

 this manner and it is the legitimate duty of the 

 paleobotanist to describe and illustrate them. 

 In order to accompUsh this work without im- 

 warranted definiteness in generic classification, 

 I propose the term Ctenomyces as a form genus 

 for leaf-spot fungi of Cenozoic age whose precise 

 botanic affinities can not be determined. I do 

 not propose to burden the literatiu-e with any 

 large number of new forms nor to make any 

 new combinations by referring species which 

 other authors have described as Sphteria and 

 the like to this genus, but I shall use the term 

 in my own studies of Tertiary floras where well- 

 marked remains of this sort require commemo- 

 ration either because of especial geologic or 

 biologic interest. Most such forms probably 

 represent the Ascomycetes. (See PI. CXI, fig. 6.) 



> From Kocjir^ recent, and ;uk);f, a fungus. 



• MeschineUi _\., Fungi (ossili^, in Saccardo's Sylloge lungonun, voL 

 10,1892. 



Cj;xojrYCES lalrixea Berry, n. sp. 

 Plate LXXXVIII, fisiire 4. 



Description. — Usuall\- situated or most ex- 

 tensively developed on or near the vascular 

 framework of the leaf and comparable with 

 modem forms that cause leaf blight by their 

 hiterfcrence with the circulation in the loaf. 

 This form is abundant on the leaves of Nectan- 

 dra Jaicii Berry, particularly along the midrib, 

 where perithecia are represented by elliptical, 

 more or less confluent masses of discoloration 

 about 3 millimeters in length and 1.5 millimeters 

 in width, evidently starting as small circular 

 spots which become elongated and rmi together, 

 since they are isolated in the upper part of the 

 leaf but form a common mass toward the base 

 of the midrib. This species resembles Depazea 

 andromedse described by Saporta ^ on a species 

 of Andromeda from the Ligurian (Sannoisian) 

 of Aix m southeastern France. 



Occurrence. — HoUy Springs sand, Oxford 

 Gullv, Lafavette County, iliss. (collected by 

 E. W. Berry). 



Collection. — U. S. National Museum. 



C^xoMTCES SAPOT^ Berry, n. sp. 

 Plate XCIX, figure 4. 



Description. — The leaves of Sideroxylon pre- 

 masticTwdendron Berry from Oxford are badly 

 infested with a leaf blight, which causes the 

 formation of irregularly oval spots that range 

 in size from 1 millimeter to 5 miUimetei-s in 

 diameter. Margins irregular and commonly 

 confluent. Perithecial masses tliick, aggre- 

 gated in the basal half of the leaf, especially 

 along the midrib. 



OccurreTice. — HoUy Springs sand, Oxford 

 Gidlv, Lafayette County, Miss. (coUected by 

 E. W. Berry). 



Collection. — U. S. National Museum. 



C^NOMYCES PESTALOZZiTES Berry, n. sp. 



Plate IX, figures 2 and 3. 



Description. — Leaf spots circular or eUiptical 

 in outline, margins generally well marked, that 

 range in size from 0.25 millimeter to 6 miUi- 

 meters, somewhat thickened and showing cout 



'Saporta, G. de, Demiferes adjonctions i la flore fossile d'Aix-en- 

 Provence, pt. 1, p. 7, pi. 9, fig. 12, 1SS9. 



