2C)G FOSSIL PLANTS FROM TEXAS FONTAINE. 



oiitiro width. In tliis l;itter R])oeiinen ;i iimnbcr of tlie leailets attacliod 

 to the riglit-hand side of tho niidiib are doubU'd over to the left-liaud 

 side, so that with casual iiispeetion they might give an erroneous idea 

 of their mocU^- of insertion. Tlie texture of the i)hint tigure<l by Scheidc 

 seems to liave beeu simihir to that of the Texas form, for both show a 

 wrinkhng- at right angles with the length of the leaflets, due to shrink- 

 ing in drying. 



It is very dithcult to seethe nerves, as they appear to be very slender 

 and are immersed in tlie leaf substance. The contraction i)roduced in 

 the fleshy leaflets gives sometimes <leceptive forms. In some cases two 

 htngitudinal folds, near the center of tlie leatlets, api>car as strong 

 nerves, and sometimes the space between them takes on tlu^ ai)pearance 

 of a strrmg single nerve, giving the ]»lant the appearance of a Cycadites. 

 At tirst 1 Avas led to think thattljc plant belongcjl to this genus. 1 am 

 not then surprised that Dunker* described a foini of this plant as Cyca- 

 dites Morrisioinis. Schenk correctly unites it with />. Dtoilrrianns, 

 notwithstanding the fact that Diinker's tigure rc]>resent.s the leaflets as 

 nearly 8 centimeters long with the cuds not preserved. 



Podozamites acutifolius Font. ? 

 I'l. xxxA I, Fig. 7. 



Only a single s])ecimen was found of a jtlant that may be identical 

 with rodoztonitcs ticiifii'oliu.s Font., of th(^ Potomac formation. This is 

 represented in ri.xxxvi. Fig. 7. It is the basal i>ortion of a small leaflet, 

 narrowing to a pedicel at base. It has (piite fine nerves that fork to 

 \var<ls the base, tli(^ branches becoming ])arall('l. The si/,e of the leaf 

 let and its shape towards the base agree (|uite w<'ll with the Potomac 

 plant,! but of course the si)ecinicn docs not permit positive identifica- 

 tion. 



It should be stated that both the si)ecies here giviMi as i'odozamites 

 may belong to the genus Nageiopsis as determined l>y the writer:]: from 

 the Potomac tloia. There are no characters in the basal jiortions of 

 single tletached leaflets that will distinguish the two geneia. The tips 

 of detached leaflets, however, show distinctions, toi- in Podozamites 

 the nerves towards th«' ends of the leatlets converge and unite more or 

 less, while in Nageiopsis they continue parallel l>nt are usually more 

 closely i)laced towards the tips. 



With reference t(> the i^cnus Nageiopsis, it may be stated that Avhen 

 its determination was made from the study (»f the abundant material 

 obtained from the Potonuic beds of Virginia, the writer had not been 

 able to see s])ecimens of the leaves of the Nageia section of Podocar- 



" " Moii()nr:i(iliie di-r Norckleiitsclien Wt-aldtMihildiuit;," )>. IG. PI. vii. Fig. 1. 

 tMoiiogiapli XV, V. S. (Jt'ologiiiil Siirvfy, Part i, text, p. 181; Part li, i)lates, PI. 

 Lxxxv, Fig. 10. 



tOj). tit.. Part I. text. !•. I!l4-li«r). 



